81168345028 has 12 divisors (see below), whose sum is σ = 142050073900. Its totient is φ = 40582609632.

The previous prime is 81168345007. The next prime is 81168345073. The reversal of 81168345028 is 82054386118.

It can be written as a sum of positive squares in 2 ways, for example, as 51084136324 + 30084208704 = 226018^2 + 173448^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 269703 + ... + 484846.

Almost surely, 2^81168345028 is an apocalyptic number.

It is an amenable number.

81168345028 is a deficient number, since it is larger than the sum of its proper divisors (60881728872).

81168345028 is a wasteful number, since it uses less digits than its factorization.

81168345028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 781446 (or 781444 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 46.

The spelling of 81168345028 in words is "eighty-one billion, one hundred sixty-eight million, three hundred forty-five thousand, twenty-eight".