51212686940416 has 81 divisors (see below), whose sum is σ = 104789042867523. Its totient is φ = 24979508490240.

The previous prime is 51212686940351. The next prime is 51212686940423. The reversal of 51212686940416 is 61404968621215.

The square root of 51212686940416 is 7156304.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 28555086940416 + 22657600000000 = 5343696^2 + 4760000^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4694529970 + ... + 4694540878.

Almost surely, 2^{51212686940416} is an apocalyptic number.

51212686940416 is the 7156304-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51212686940416

51212686940416 is an abundant number, since it is smaller than the sum of its proper divisors (53576355927107).

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

51212686940416 is an frugal number, since it uses more digits than its factorization.

51212686940416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21916 (or 10952 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 55.

The spelling of 51212686940416 in words is "fifty-one trillion, two hundred twelve billion, six hundred eighty-six million, nine hundred forty thousand, four hundred sixteen".