81370351515 has 16 divisors (see below), whose sum is σ = 130197424896. Its totient is φ = 43395900000.

The previous prime is 81370351507. The next prime is 81370351571. The reversal of 81370351515 is 51515307318.

It is not a de Polignac number, because 81370351515 - 2³ = 81370351507 is a prime.

It is a super-2 number, since 2×81370351515² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 390840 + ... + 561690.

It is an arithmetic number, because the mean of its divisors is an integer number (8137339056).

Almost surely, 2^81370351515 is an apocalyptic number.

81370351515 is a deficient number, since it is larger than the sum of its proper divisors (48827073381).

81370351515 is a wasteful number, since it uses less digits than its factorization.

81370351515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202610.

The product of its (nonzero) digits is 63000, while the sum is 39.

The spelling of 81370351515 in words is "eighty-one billion, three hundred seventy million, three hundred fifty-one thousand, five hundred fifteen".