133381864 has 128 divisors (see below), whose sum is σ = 338411520. Its totient is φ = 47692800.

The previous prime is 133381819. The next prime is 133381879. The reversal of 133381864 is 468183331.

It is a super-2 number, since 2×133381864² = 35581443288228992, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 492049 + ... + 492319.

It is an arithmetic number, because the mean of its divisors is an integer number (2643840).

Almost surely, 2^133381864 is an apocalyptic number.

133381864 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 133381864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (169205760).

133381864 is an abundant number, since it is smaller than the sum of its proper divisors (205029656).

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

133381864 is a wasteful number, since it uses less digits than its factorization.

133381864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 359 (or 355 counting only the distinct ones).

The product of its digits is 41472, while the sum is 37.

The square root of 133381864 is about 11549.1066321166. The cubic root of 133381864 is about 510.9349299231.

The spelling of 133381864 in words is "one hundred thirty-three million, three hundred eighty-one thousand, eight hundred sixty-four".