51577320 has 128 divisors (see below), whose sum is σ = 165939840. Its totient is φ = 12779520.

The previous prime is 51577319. The next prime is 51577327. The reversal of 51577320 is 2377515.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (51577327) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 267144 + ... + 267336.

It is an arithmetic number, because the mean of its divisors is an integer number (1296405).

Almost surely, 2^51577320 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 51577320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82969920).

51577320 is an abundant number, since it is smaller than the sum of its proper divisors (114362520).

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

51577320 is a wasteful number, since it uses less digits than its factorization.

51577320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355 (or 351 counting only the distinct ones).

The product of its (nonzero) digits is 7350, while the sum is 30.

The square root of 51577320 is about 7181.7351663787. The cubic root of 51577320 is about 372.2370439714.

The spelling of 51577320 in words is "fifty-one million, five hundred seventy-seven thousand, three hundred twenty".