81751287940968 has 16 divisors (see below), whose sum is σ = 204378219852480. Its totient is φ = 27250429313648.

The previous prime is 81751287940957. The next prime is 81751287940991. The reversal of 81751287940968 is 86904978215718.

It is a self number, because there is not a number n which added to its sum of digits gives 81751287940968.

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, 1703151832080 + ... + 1703151832127.

It is an arithmetic number, because the mean of its divisors is an integer number (12773638740780).

Almost surely, 2^{81751287940968} is an apocalyptic number.

It is an amenable number.

81751287940968 is an abundant number, since it is smaller than the sum of its proper divisors (122626931911512).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81751287940968 is a wasteful number, since it uses less digits than its factorization.

81751287940968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3406303664216 (or 3406303664212 counting only the distinct ones).

The product of its (nonzero) digits is 487710720, while the sum is 75.

The spelling of 81751287940968 in words is "eighty-one trillion, seven hundred fifty-one billion, two hundred eighty-seven million, nine hundred forty thousand, nine hundred sixty-eight".