81013691290 has 32 divisors (see below), whose sum is σ = 170721540864. Its totient is φ = 27098655360.

The previous prime is 81013691237. The next prime is 81013691333. The reversal of 81013691290 is 9219631018.

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, 14111014 + ... + 14116753.

It is an arithmetic number, because the mean of its divisors is an integer number (5335048152).

Almost surely, 2^81013691290 is an apocalyptic number.

81013691290 is an abundant number, since it is smaller than the sum of its proper divisors (89707849574).

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

81013691290 is a wasteful number, since it uses less digits than its factorization.

81013691290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28227822.

The product of its (nonzero) digits is 23328, while the sum is 40.

The spelling of 81013691290 in words is "eighty-one billion, thirteen million, six hundred ninety-one thousand, two hundred ninety".