55772928 has 72 divisors (see below), whose sum is σ = 164950800. Its totient is φ = 18588672.

The previous prime is 55772921. The next prime is 55772933. The reversal of 55772928 is 82927755.

It is a happy number.

55772928 is a `hidden beast` number, since 557 + 7 + 2 + 92 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×55772928² = 6221238995386368, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55772921) 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, 2878 + ... + 10946.

Almost surely, 2^55772928 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 55772928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82475400).

55772928 is an abundant number, since it is smaller than the sum of its proper divisors (109177872).

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

55772928 is an equidigital number, since it uses as much as digits as its factorization.

55772928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8094 (or 8074 counting only the distinct ones).

The product of its digits is 352800, while the sum is 45.

The square root of 55772928 is about 7468.1274761482. The cubic root of 55772928 is about 382.0684251942.

The spelling of 55772928 in words is "fifty-five million, seven hundred seventy-two thousand, nine hundred twenty-eight".