81222221490 has 32 divisors (see below), whose sum is σ = 194940919296. Its totient is φ = 21658416000.

The previous prime is 81222221489. The next prime is 81222221519. The reversal of 81222221490 is 9412222218.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1300990 + ... + 1361990.

It is an arithmetic number, because the mean of its divisors is an integer number (6091903728).

Almost surely, 2^81222221490 is an apocalyptic number.

81222221490 is an abundant number, since it is smaller than the sum of its proper divisors (113718697806).

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

81222221490 is a wasteful number, since it uses less digits than its factorization.

81222221490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105394.

The product of its (nonzero) digits is 9216, while the sum is 33.

The spelling of 81222221490 in words is "eighty-one billion, two hundred twenty-two million, two hundred twenty-one thousand, four hundred ninety".