51666587518616 has 32 divisors (see below), whose sum is σ = 110794752923040. Its totient is φ = 22126695859968.

The previous prime is 51666587518591. The next prime is 51666587518633. The reversal of 51666587518616 is 61681578566615.

It is a super-2 number, since 2×51666587518616² (a number of 28 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (71) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 51666587518616.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 335909141 + ... + 336062916.

It is an arithmetic number, because the mean of its divisors is an integer number (3462336028845).

Almost surely, 2^{51666587518616} is an apocalyptic number.

51666587518616 is a gapful number since it is divisible by the number (56) formed by its first and last digit.

It is an amenable number.

51666587518616 is an abundant number, since it is smaller than the sum of its proper divisors (59128165404424).

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

51666587518616 is a wasteful number, since it uses less digits than its factorization.

51666587518616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 671973443 (or 671973439 counting only the distinct ones).

The product of its digits is 435456000, while the sum is 71.

The spelling of 51666587518616 in words is "fifty-one trillion, six hundred sixty-six billion, five hundred eighty-seven million, five hundred eighteen thousand, six hundred sixteen".