81611753290 has 48 divisors (see below), whose sum is σ = 158380199712. Its totient is φ = 30265779456.

The previous prime is 81611753263. The next prime is 81611753291. The reversal of 81611753290 is 9235711618.

It is not an unprimeable number, because it can be changed into a prime (81611753291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17112 + ... + 404371.

It is an arithmetic number, because the mean of its divisors is an integer number (3299587494).

Almost surely, 2^81611753290 is an apocalyptic number.

81611753290 is a deficient number, since it is larger than the sum of its proper divisors (76768446422).

81611753290 is a wasteful number, since it uses less digits than its factorization.

81611753290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 421591 (or 421574 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 43.

The spelling of 81611753290 in words is "eighty-one billion, six hundred eleven million, seven hundred fifty-three thousand, two hundred ninety".