55778888 has 32 divisors (see below), whose sum is σ = 115974720. Its totient is φ = 24936000.

The previous prime is 55778867. The next prime is 55778909. The reversal of 55778888 is 88887755.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (55778867) and next prime (55778909).

It is a super-2 number, since 2×55778888² = 6222568693033088, which contains 22 as substring.

It is a plaindrome in base 10.

It is a zygodrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 173 + ... + 10563.

It is an arithmetic number, because the mean of its divisors is an integer number (3624210).

Almost surely, 2^55778888 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 55778888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57987360).

55778888 is an abundant number, since it is smaller than the sum of its proper divisors (60195832).

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

55778888 is a wasteful number, since it uses less digits than its factorization.

55778888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10469 (or 10465 counting only the distinct ones).

The product of its digits is 5017600, while the sum is 56.

The square root of 55778888 is about 7468.5264945637. The cubic root of 55778888 is about 382.0820342263.

The spelling of 55778888 in words is "fifty-five million, seven hundred seventy-eight thousand, eight hundred eighty-eight".