81351642984 has 16 divisors (see below), whose sum is σ = 203379107520. Its totient is φ = 27117214320.

The previous prime is 81351642979. The next prime is 81351642997. The reversal of 81351642984 is 48924615318.

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, 1694825872 + ... + 1694825919.

It is an arithmetic number, because the mean of its divisors is an integer number (12711194220).

Almost surely, 2^81351642984 is an apocalyptic number.

It is an amenable number.

81351642984 is an abundant number, since it is smaller than the sum of its proper divisors (122027464536).

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

81351642984 is a wasteful number, since it uses less digits than its factorization.

81351642984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3389651800 (or 3389651796 counting only the distinct ones).

The product of its digits is 1658880, while the sum is 51.

The spelling of 81351642984 in words is "eighty-one billion, three hundred fifty-one million, six hundred forty-two thousand, nine hundred eighty-four".