55581531 has 8 divisors (see below), whose sum is σ = 75001920. Its totient is φ = 36607752.

The previous prime is 55581529. The next prime is 55581541. The reversal of 55581531 is 13518555.

55581531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 55581531 - 2¹ = 55581529 is a prime.

It is a super-2 number, since 2×55581531² = 6178613176607922, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 55581492 and 55581501.

It is not an unprimeable number, because it can be changed into a prime (55581541) 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 7 ways as a sum of consecutive naturals, for example, 111361 + ... + 111858.

It is an arithmetic number, because the mean of its divisors is an integer number (9375240).

Almost surely, 2^55581531 is an apocalyptic number.

55581531 is a deficient number, since it is larger than the sum of its proper divisors (19420389).

55581531 is a wasteful number, since it uses less digits than its factorization.

55581531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223305.

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

The square root of 55581531 is about 7455.3022071543. The cubic root of 55581531 is about 381.6308738409.

The spelling of 55581531 in words is "fifty-five million, five hundred eighty-one thousand, five hundred thirty-one".