51258564 has 72 divisors (see below), whose sum is σ = 149542848. Its totient is φ = 14500800.

The previous prime is 51258563. The next prime is 51258607. The reversal of 51258564 is 46585215.

51258564 is a `hidden beast` number, since 5 + 12 + 585 + 64 = 666.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (51258563) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26014 + ... + 27914.

It is an arithmetic number, because the mean of its divisors is an integer number (2076984).

Almost surely, 2^51258564 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 51258564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (74771424).

51258564 is an abundant number, since it is smaller than the sum of its proper divisors (98284284).

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

51258564 is a wasteful number, since it uses less digits than its factorization.

51258564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2025 (or 2020 counting only the distinct ones).

The product of its digits is 48000, while the sum is 36.

The square root of 51258564 is about 7159.5086423581. The cubic root of 51258564 is about 371.4686308724.

It can be divided in two parts, 5125 and 8564, that added together give a square (13689 = 117²).

The spelling of 51258564 in words is "fifty-one million, two hundred fifty-eight thousand, five hundred sixty-four".