51515013540 has 48 divisors (see below), whose sum is σ = 144300780288. Its totient is φ = 13731742464.

The previous prime is 51515013497. The next prime is 51515013551. The reversal of 51515013540 is 4531051515.

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

It is a junction number, because it is equal to n+sod(n) for n = 51515013498 and 51515013507.

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, 25212 + ... + 321971.

It is an arithmetic number, because the mean of its divisors is an integer number (3006266256).

Almost surely, 2^51515013540 is an apocalyptic number.

It is an amenable number.

51515013540 is an abundant number, since it is smaller than the sum of its proper divisors (92785766748).

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

51515013540 is a wasteful number, since it uses less digits than its factorization.

51515013540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 349668 (or 349666 counting only the distinct ones).

The product of its (nonzero) digits is 7500, while the sum is 30.

The spelling of 51515013540 in words is "fifty-one billion, five hundred fifteen million, thirteen thousand, five hundred forty".