81040117850 has 24 divisors (see below), whose sum is σ = 155597029248. Its totient is φ = 31370367600.

The previous prime is 81040117843. The next prime is 81040117871. The reversal of 81040117850 is 5871104018.

It is a super-2 number, since 2×81040117850² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81040117850.

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, 26140424 + ... + 26143523.

It is an arithmetic number, because the mean of its divisors is an integer number (6483209552).

Almost surely, 2^81040117850 is an apocalyptic number.

81040117850 is a deficient number, since it is larger than the sum of its proper divisors (74556911398).

81040117850 is a wasteful number, since it uses less digits than its factorization.

81040117850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52283990 (or 52283985 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 35.

The spelling of 81040117850 in words is "eighty-one billion, forty million, one hundred seventeen thousand, eight hundred fifty".