51420720 has 80 divisors (see below), whose sum is σ = 171676512. Its totient is φ = 12656640.

The previous prime is 51420703. The next prime is 51420727. The reversal of 51420720 is 2702415.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-3 number, since 3×51420720³ (a number of 24 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (51420727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5121 + ... + 11360.

Almost surely, 2^51420720 is an apocalyptic number.

It is an amenable number.

51420720 is an abundant number, since it is smaller than the sum of its proper divisors (120255792).

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

51420720 is a wasteful number, since it uses less digits than its factorization.

51420720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16510 (or 16504 counting only the distinct ones).

The product of its (nonzero) digits is 560, while the sum is 21.

The square root of 51420720 is about 7170.8242204087. The cubic root of 51420720 is about 371.8599310797.

The spelling of 51420720 in words is "fifty-one million, four hundred twenty thousand, seven hundred twenty".