81496536399 has 66 divisors (see below), whose sum is σ = 126788352288. Its totient is φ = 52329223800.

The previous prime is 81496536389. The next prime is 81496536409. The reversal of 81496536399 is 99363569418.

81496536399 is a `hidden beast` number, since 8 + 1 + 4 + 9 + 6 + 536 + 3 + 99 = 666.

It is an interprime number because it is at equal distance from previous prime (81496536389) and next prime (81496536409).

It is not a de Polignac number, because 81496536399 - 2¹² = 81496532303 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81496536349) by changing a digit.

It is a polite number, since it can be written in 65 ways as a sum of consecutive naturals, for example, 386239404 + ... + 386239614.

Almost surely, 2^81496536399 is an apocalyptic number.

81496536399 is a deficient number, since it is larger than the sum of its proper divisors (45291815889).

81496536399 is an frugal number, since it uses more digits than its factorization.

81496536399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 483 (or 245 counting only the distinct ones).

The product of its digits is 37791360, while the sum is 63.

The spelling of 81496536399 in words is "eighty-one billion, four hundred ninety-six million, five hundred thirty-six thousand, three hundred ninety-nine".