78751662113381 has 2 divisors, whose sum is σ = 78751662113382. Its totient is φ = 78751662113380.

The previous prime is 78751662113309. The next prime is 78751662113419. The reversal of 78751662113381 is 18331126615787.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63212692310881 + 15538969802500 = 7950641^2 + 3941950^2 .

It is a cyclic number.

It is not a de Polignac number, because 78751662113381 - 2¹⁴ = 78751662096997 is a prime.

It is a super-2 number, since 2×78751662113381² (a number of 29 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 78751662113381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78751662113281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39375831056690 + 39375831056691.

It is an arithmetic number, because the mean of its divisors is an integer number (39375831056691).

Almost surely, 2^{78751662113381} is an apocalyptic number.

It is an amenable number.

78751662113381 is a deficient number, since it is larger than the sum of its proper divisors (1).

78751662113381 is an equidigital number, since it uses as much as digits as its factorization.

78751662113381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10160640, while the sum is 59.

The spelling of 78751662113381 in words is "seventy-eight trillion, seven hundred fifty-one billion, six hundred sixty-two million, one hundred thirteen thousand, three hundred eighty-one".