55581031 has 4 divisors (see below), whose sum is σ = 60633864. Its totient is φ = 50528200.

The previous prime is 55581017. The next prime is 55581083. The reversal of 55581031 is 13018555.

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 55581031 - 2⁵ = 55580999 is a prime.

It is a super-2 number, since 2×55581031² = 6178502014045922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55581131) 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, 2526400 + ... + 2526421.

It is an arithmetic number, because the mean of its divisors is an integer number (15158466).

Almost surely, 2^55581031 is an apocalyptic number.

55581031 is a deficient number, since it is larger than the sum of its proper divisors (5052833).

55581031 is a wasteful number, since it uses less digits than its factorization.

55581031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5052832.

The product of its (nonzero) digits is 3000, while the sum is 28.

The square root of 55581031 is about 7455.2686738977. The cubic root of 55581031 is about 381.6297294799.

Adding to 55581031 its reverse (13018555), we get a palindrome (68599586).

The spelling of 55581031 in words is "fifty-five million, five hundred eighty-one thousand, thirty-one".