51615660 has 48 divisors (see below), whose sum is σ = 144992736. Its totient is φ = 13719552.

The previous prime is 51615659. The next prime is 51615673. The reversal of 51615660 is 6651615.

It is a super-3 number, since 3×51615660³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 19962 + ... + 22398.

It is an arithmetic number, because the mean of its divisors is an integer number (3020682).

Almost surely, 2^51615660 is an apocalyptic number.

It is an amenable number.

51615660 is an abundant number, since it is smaller than the sum of its proper divisors (93377076).

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

51615660 is a wasteful number, since it uses less digits than its factorization.

51615660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2802 (or 2800 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 30.

The square root of 51615660 is about 7184.4039418730. The cubic root of 51615660 is about 372.3292552603.

The spelling of 51615660 in words is "fifty-one million, six hundred fifteen thousand, six hundred sixty".