133631904 has 96 divisors (see below), whose sum is σ = 409522176. Its totient is φ = 37359360.

The previous prime is 133631903. The next prime is 133631923. The reversal of 133631904 is 409136331.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (133631903) 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, 29469 + ... + 33699.

It is an arithmetic number, because the mean of its divisors is an integer number (4265856).

Almost surely, 2^133631904 is an apocalyptic number.

133631904 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 133631904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (204761088).

133631904 is an abundant number, since it is smaller than the sum of its proper divisors (275890272).

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

133631904 is a wasteful number, since it uses less digits than its factorization.

133631904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4298 (or 4290 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 30.

The square root of 133631904 is about 11559.9266433659. The cubic root of 133631904 is about 511.2539998452.

The spelling of 133631904 in words is "one hundred thirty-three million, six hundred thirty-one thousand, nine hundred four".