55421556 has 24 divisors (see below), whose sum is σ = 136123680. Its totient is φ = 17501472.

The previous prime is 55421551. The next prime is 55421557. The reversal of 55421556 is 65512455.

It is a super-2 number, since 2×55421556² = 6143097738922272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55421551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 121311 + ... + 121766.

It is an arithmetic number, because the mean of its divisors is an integer number (5671820).

Almost surely, 2^55421556 is an apocalyptic number.

It is an amenable number.

55421556 is an abundant number, since it is smaller than the sum of its proper divisors (80702124).

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

55421556 is a wasteful number, since it uses less digits than its factorization.

55421556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243103 (or 243101 counting only the distinct ones).

The product of its digits is 30000, while the sum is 33.

The square root of 55421556 is about 7444.5655346702. The cubic root of 55421556 is about 381.2643848017.

The spelling of 55421556 in words is "fifty-five million, four hundred twenty-one thousand, five hundred fifty-six".