55390857 has 16 divisors (see below), whose sum is σ = 74954880. Its totient is φ = 36381312.

The previous prime is 55390849. The next prime is 55390889. The reversal of 55390857 is 75809355.

It is not a de Polignac number, because 55390857 - 2³ = 55390849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (55390817) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75828 + ... + 76554.

It is an arithmetic number, because the mean of its divisors is an integer number (4684680).

Almost surely, 2^55390857 is an apocalyptic number.

It is an amenable number.

55390857 is a deficient number, since it is larger than the sum of its proper divisors (19564023).

55390857 is a wasteful number, since it uses less digits than its factorization.

55390857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1072.

The product of its (nonzero) digits is 189000, while the sum is 42.

The square root of 55390857 is about 7442.5034094718. The cubic root of 55390857 is about 381.1939753921.

The spelling of 55390857 in words is "fifty-five million, three hundred ninety thousand, eight hundred fifty-seven".