133242531 has 4 divisors (see below), whose sum is σ = 177656712. Its totient is φ = 88828352.

The previous prime is 133242521. The next prime is 133242539. The reversal of 133242531 is 135242331.

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 133242531 - 2⁶ = 133242467 is a prime.

It is a super-2 number, since 2×133242531² = 35507144134571922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (133242539) 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, 22207086 + ... + 22207091.

It is an arithmetic number, because the mean of its divisors is an integer number (44414178).

Almost surely, 2^133242531 is an apocalyptic number.

133242531 is a deficient number, since it is larger than the sum of its proper divisors (44414181).

133242531 is an equidigital number, since it uses as much as digits as its factorization.

133242531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44414180.

The product of its digits is 2160, while the sum is 24.

The square root of 133242531 is about 11543.0728577792. The cubic root of 133242531 is about 510.7569574521.

Adding to 133242531 its reverse (135242331), we get a palindrome (268484862).

The spelling of 133242531 in words is "one hundred thirty-three million, two hundred forty-two thousand, five hundred thirty-one".