51721736 has 16 divisors (see below), whose sum is σ = 105794640. Its totient is φ = 23509840.

The previous prime is 51721721. The next prime is 51721739. The reversal of 51721736 is 63712715.

It is not an unprimeable number, because it can be changed into a prime (51721739) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 293786 + ... + 293961.

It is an arithmetic number, because the mean of its divisors is an integer number (6612165).

Almost surely, 2^51721736 is an apocalyptic number.

It is an amenable number.

51721736 is an abundant number, since it is smaller than the sum of its proper divisors (54072904).

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

51721736 is a wasteful number, since it uses less digits than its factorization.

51721736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 587764 (or 587760 counting only the distinct ones).

The product of its digits is 8820, while the sum is 32.

The square root of 51721736 is about 7191.7825328635. The cubic root of 51721736 is about 372.5841402651.

The spelling of 51721736 in words is "fifty-one million, seven hundred twenty-one thousand, seven hundred thirty-six".