56815550 has 36 divisors (see below), whose sum is σ = 116169648. Its totient is φ = 20658000.

The previous prime is 56815541. The next prime is 56815559. The reversal of 56815550 is 5551865.

It is an interprime number because it is at equal distance from previous prime (56815541) and next prime (56815559).

It is a self number, because there is not a number n which added to its sum of digits gives 56815550.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56815559) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1355 + ... + 10745.

Almost surely, 2^56815550 is an apocalyptic number.

56815550 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

56815550 is an abundant number, since it is smaller than the sum of its proper divisors (59354098).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

56815550 is a wasteful number, since it uses less digits than its factorization.

56815550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9425 (or 9409 counting only the distinct ones).

The product of its (nonzero) digits is 30000, while the sum is 35.

The square root of 56815550 is about 7537.6090373540. The cubic root of 56815550 is about 384.4345440617.

The spelling of 56815550 in words is "fifty-six million, eight hundred fifteen thousand, five hundred fifty".