51021501540 has 48 divisors (see below), whose sum is σ = 142939829760. Its totient is φ = 13598150400.

The previous prime is 51021501539. The next prime is 51021501563. The reversal of 51021501540 is 4510512015.

It is a self number, because there is not a number n which added to its sum of digits gives 51021501540.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 128020 + ... + 344139.

It is an arithmetic number, because the mean of its divisors is an integer number (2977913120).

Almost surely, 2^51021501540 is an apocalyptic number.

It is an amenable number.

51021501540 is an abundant number, since it is smaller than the sum of its proper divisors (91918328220).

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

51021501540 is a wasteful number, since it uses less digits than its factorization.

51021501540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 473972 (or 473970 counting only the distinct ones).

The product of its (nonzero) digits is 1000, while the sum is 24.

The spelling of 51021501540 in words is "fifty-one billion, twenty-one million, five hundred one thousand, five hundred forty".