133216931 has 4 divisors (see below), whose sum is σ = 135730512. Its totient is φ = 130703352.

The previous prime is 133216921. The next prime is 133216933. The reversal of 133216931 is 139612331.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 133216931 - 2²⁶ = 66108067 is a prime.

It is a super-2 number, since 2×133216931² = 35493501410117522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 133216894 and 133216903.

It is not an unprimeable number, because it can be changed into a prime (133216933) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1256711 + ... + 1256816.

It is an arithmetic number, because the mean of its divisors is an integer number (33932628).

Almost surely, 2^133216931 is an apocalyptic number.

133216931 is a deficient number, since it is larger than the sum of its proper divisors (2513581).

133216931 is an equidigital number, since it uses as much as digits as its factorization.

133216931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2513580.

The product of its digits is 2916, while the sum is 29.

The square root of 133216931 is about 11541.9639143432. The cubic root of 133216931 is about 510.7242446351.

The spelling of 133216931 in words is "one hundred thirty-three million, two hundred sixteen thousand, nine hundred thirty-one".