81316860739 has 2 divisors, whose sum is σ = 81316860740. Its totient is φ = 81316860738.

The previous prime is 81316860689. The next prime is 81316860773. The reversal of 81316860739 is 93706861318.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81316860739 - 2¹⁵ = 81316827971 is a prime.

It is a super-2 number, since 2×81316860739² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81316860799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40658430369 + 40658430370.

It is an arithmetic number, because the mean of its divisors is an integer number (40658430370).

Almost surely, 2^81316860739 is an apocalyptic number.

81316860739 is a deficient number, since it is larger than the sum of its proper divisors (1).

81316860739 is an equidigital number, since it uses as much as digits as its factorization.

81316860739 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1306368, while the sum is 52.

The spelling of 81316860739 in words is "eighty-one billion, three hundred sixteen million, eight hundred sixty thousand, seven hundred thirty-nine".