81397835279 has 8 divisors (see below), whose sum is σ = 82232003040. Its totient is φ = 80565256800.

The previous prime is 81397835249. The next prime is 81397835287. The reversal of 81397835279 is 97253879318.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81397835279 - 2²⁴ = 81381058063 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81397835209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 294227 + ... + 499364.

It is an arithmetic number, because the mean of its divisors is an integer number (10279000380).

Almost surely, 2^81397835279 is an apocalyptic number.

81397835279 is a deficient number, since it is larger than the sum of its proper divisors (834167761).

81397835279 is a wasteful number, since it uses less digits than its factorization.

81397835279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 794641.

The product of its digits is 22861440, while the sum is 62.

The spelling of 81397835279 in words is "eighty-one billion, three hundred ninety-seven million, eight hundred thirty-five thousand, two hundred seventy-nine".