81942912015 has 96 divisors (see below), whose sum is σ = 146476693440. Its totient is φ = 38975827968.

The previous prime is 81942912001. The next prime is 81942912071. The reversal of 81942912015 is 51021924918.

It is not a de Polignac number, because 81942912015 - 2⁵ = 81942911983 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 14700769 + ... + 14706341.

It is an arithmetic number, because the mean of its divisors is an integer number (1525798890).

Almost surely, 2^81942912015 is an apocalyptic number.

81942912015 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

81942912015 is a deficient number, since it is larger than the sum of its proper divisors (64533781425).

81942912015 is a wasteful number, since it uses less digits than its factorization.

81942912015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5753 (or 5730 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 42.

The spelling of 81942912015 in words is "eighty-one billion, nine hundred forty-two million, nine hundred twelve thousand, fifteen".