55518531 has 16 divisors (see below), whose sum is σ = 74895360. Its totient is φ = 36580320.

The previous prime is 55518523. The next prime is 55518539. The reversal of 55518531 is 13581555.

55518531 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 (55518523) and next prime (55518539).

It is not a de Polignac number, because 55518531 - 2³ = 55518523 is a prime.

It is a super-2 number, since 2×55518531² = 6164614568795922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 55518492 and 55518501.

It is not an unprimeable number, because it can be changed into a prime (55518539) 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 15 ways as a sum of consecutive naturals, for example, 144766 + ... + 145148.

It is an arithmetic number, because the mean of its divisors is an integer number (4680960).

Almost surely, 2^55518531 is an apocalyptic number.

55518531 is a deficient number, since it is larger than the sum of its proper divisors (19376829).

55518531 is a wasteful number, since it uses less digits than its factorization.

55518531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 826.

The product of its digits is 15000, while the sum is 33.

The square root of 55518531 is about 7451.0758283620. The cubic root of 55518531 is about 381.4866302750.

The spelling of 55518531 in words is "fifty-five million, five hundred eighteen thousand, five hundred thirty-one".