51521215545 has 96 divisors (see below), whose sum is σ = 95622718464. Its totient is φ = 25614144000.

The previous prime is 51521215541. The next prime is 51521215583. The reversal of 51521215545 is 54551212515.

51521215545 is a `hidden beast` number, since 51 + 52 + 1 + 2 + 1 + 554 + 5 = 666.

It is not a de Polignac number, because 51521215545 - 2² = 51521215541 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51521215541) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 5208174 + ... + 5218056.

It is an arithmetic number, because the mean of its divisors is an integer number (996069984).

Almost surely, 2^51521215545 is an apocalyptic number.

It is an amenable number.

51521215545 is a deficient number, since it is larger than the sum of its proper divisors (44101502919).

51521215545 is a wasteful number, since it uses less digits than its factorization.

51521215545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10063 (or 10060 counting only the distinct ones).

The product of its digits is 50000, while the sum is 36.

The spelling of 51521215545 in words is "fifty-one billion, five hundred twenty-one million, two hundred fifteen thousand, five hundred forty-five".