133517231 has 4 divisors (see below), whose sum is σ = 139322352. Its totient is φ = 127712112.

The previous prime is 133517183. The next prime is 133517233. The reversal of 133517231 is 132715331.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 132715331 = 7 ⋅18959333.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-133517231 is a prime.

It is a super-2 number, since 2×133517231² = 35653701947814722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 133517231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133517233) 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, 2902526 + ... + 2902571.

It is an arithmetic number, because the mean of its divisors is an integer number (34830588).

Almost surely, 2^133517231 is an apocalyptic number.

133517231 is a deficient number, since it is larger than the sum of its proper divisors (5805121).

133517231 is an equidigital number, since it uses as much as digits as its factorization.

133517231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5805120.

The product of its digits is 1890, while the sum is 26.

The square root of 133517231 is about 11554.9656425279. The cubic root of 133517231 is about 511.1077178921.

The spelling of 133517231 in words is "one hundred thirty-three million, five hundred seventeen thousand, two hundred thirty-one".