81072317850 has 24 divisors (see below), whose sum is σ = 201059348640. Its totient is φ = 21619284720.

The previous prime is 81072317849. The next prime is 81072317861. The reversal of 81072317850 is 5871327018.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 270240910 + ... + 270241209.

It is an arithmetic number, because the mean of its divisors is an integer number (8377472860).

Almost surely, 2^81072317850 is an apocalyptic number.

81072317850 is an abundant number, since it is smaller than the sum of its proper divisors (119987030790).

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

81072317850 is a wasteful number, since it uses less digits than its factorization.

81072317850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540482134 (or 540482129 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 42.

The spelling of 81072317850 in words is "eighty-one billion, seventy-two million, three hundred seventeen thousand, eight hundred fifty".