51621264 has 60 divisors (see below), whose sum is σ = 145563600. Its totient is φ = 17076672.

The previous prime is 51621257. The next prime is 51621281. The reversal of 51621264 is 46212615.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18727 + ... + 21305.

It is an arithmetic number, because the mean of its divisors is an integer number (2426060).

Almost surely, 2^51621264 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 51621264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72781800).

51621264 is an abundant number, since it is smaller than the sum of its proper divisors (93942336).

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

51621264 is a wasteful number, since it uses less digits than its factorization.

51621264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2732 (or 2723 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 51621264 is about 7184.7939427655. The cubic root of 51621264 is about 372.3427295795.

Adding to 51621264 its reverse (46212615), we get a palindrome (97833879).

The spelling of 51621264 in words is "fifty-one million, six hundred twenty-one thousand, two hundred sixty-four".