133211904 has 144 divisors (see below), whose sum is σ = 412070400. Its totient is φ = 37416960.

The previous prime is 133211899. The next prime is 133211909. The reversal of 133211904 is 409112331.

133211904 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (133211899) and next prime (133211909).

It is a super-2 number, since 2×133211904² = 35490822734610432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133211909) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 381522 + ... + 381870.

It is an arithmetic number, because the mean of its divisors is an integer number (2861600).

Almost surely, 2^133211904 is an apocalyptic number.

133211904 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 133211904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (206035200).

133211904 is an abundant number, since it is smaller than the sum of its proper divisors (278858496).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

133211904 is an equidigital number, since it uses as much as digits as its factorization.

133211904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 446 (or 432 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 133211904 is about 11541.7461417240. The cubic root of 133211904 is about 510.7178204190.

It can be divided in two parts, 13321 and 1904, that added together give a triangular number (15225 = T₁₇₄).

The spelling of 133211904 in words is "one hundred thirty-three million, two hundred eleven thousand, nine hundred four".