55001556 has 72 divisors (see below), whose sum is σ = 146275584. Its totient is φ = 17392320.

The previous prime is 55001549. The next prime is 55001567. The reversal of 55001556 is 65510055.

55001556 is a `hidden beast` number, since 5 + 500 + 155 + 6 = 666.

It is a super-2 number, since 2×55001556² = 6050342324842272, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 149685 + ... + 150051.

Almost surely, 2^55001556 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55001556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73137792).

55001556 is an abundant number, since it is smaller than the sum of its proper divisors (91274028).

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

55001556 is a wasteful number, since it uses less digits than its factorization.

55001556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 581 (or 576 counting only the distinct ones).

The product of its (nonzero) digits is 3750, while the sum is 27.

The square root of 55001556 is about 7416.3033918523. The cubic root of 55001556 is about 380.2988323417.

It can be divided in two parts, 5500 and 1556, that added together give a square (7056 = 84²).

The spelling of 55001556 in words is "fifty-five million, one thousand, five hundred fifty-six".