51729720 has 64 divisors (see below), whose sum is σ = 177361920. Its totient is φ = 11823744.

The previous prime is 51729709. The next prime is 51729757. The reversal of 51729720 is 2792715.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29952 + ... + 31631.

It is an arithmetic number, because the mean of its divisors is an integer number (2771280).

Almost surely, 2^51729720 is an apocalyptic number.

It is an amenable number.

51729720 is an abundant number, since it is smaller than the sum of its proper divisors (125632200).

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

51729720 is a wasteful number, since it uses less digits than its factorization.

51729720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61604 (or 61600 counting only the distinct ones).

The product of its (nonzero) digits is 8820, while the sum is 33.

The square root of 51729720 is about 7192.3375894072. The cubic root of 51729720 is about 372.6033105337.

The spelling of 51729720 in words is "fifty-one million, seven hundred twenty-nine thousand, seven hundred twenty".