55133531 has 12 divisors (see below), whose sum is σ = 57625776. Its totient is φ = 52742160.

The previous prime is 55133513. The next prime is 55133549. The reversal of 55133531 is 13533155.

55133531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (55133513) and next prime (55133549).

It is not a de Polignac number, because 55133531 - 2⁶ = 55133467 is a prime.

It is a super-2 number, since 2×55133531² = 6079412481055922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 55133531.

It is not an unprimeable number, because it can be changed into a prime (55133501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 98705 + ... + 99261.

It is an arithmetic number, because the mean of its divisors is an integer number (4802148).

Almost surely, 2^55133531 is an apocalyptic number.

55133531 is a deficient number, since it is larger than the sum of its proper divisors (2492245).

55133531 is a wasteful number, since it uses less digits than its factorization.

55133531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 722 (or 691 counting only the distinct ones).

The product of its digits is 3375, while the sum is 26.

The square root of 55133531 is about 7425.1956876570. The cubic root of 55133531 is about 380.6027622197.

Adding to 55133531 its reverse (13533155), we get a palindrome (68666686).

The spelling of 55133531 in words is "fifty-five million, one hundred thirty-three thousand, five hundred thirty-one".