55778028 has 12 divisors (see below), whose sum is σ = 130148760. Its totient is φ = 18592672.

The previous prime is 55778027. The next prime is 55778087. The reversal of 55778028 is 82087755.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×55778028² = 6222376815137568, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (55778027) 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, 2324073 + ... + 2324096.

It is an arithmetic number, because the mean of its divisors is an integer number (10845730).

Almost surely, 2^55778028 is an apocalyptic number.

It is an amenable number.

55778028 is an abundant number, since it is smaller than the sum of its proper divisors (74370732).

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

55778028 is a wasteful number, since it uses less digits than its factorization.

55778028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4648176 (or 4648174 counting only the distinct ones).

The product of its (nonzero) digits is 156800, while the sum is 42.

The square root of 55778028 is about 7468.4689193971. The cubic root of 55778028 is about 382.0800705667.

The spelling of 55778028 in words is "fifty-five million, seven hundred seventy-eight thousand, twenty-eight".