81595999990 has 16 divisors (see below), whose sum is σ = 146876055840. Its totient is φ = 32637676480.

The previous prime is 81595999913. The next prime is 81596000033. The reversal of 81595999990 is 9999959518.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 812466 + ... + 907354.

It is an arithmetic number, because the mean of its divisors is an integer number (9179753490).

Almost surely, 2^81595999990 is an apocalyptic number.

81595999990 is a deficient number, since it is larger than the sum of its proper divisors (65280055850).

81595999990 is a wasteful number, since it uses less digits than its factorization.

81595999990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180887.

The product of its (nonzero) digits is 106288200, while the sum is 73.

The spelling of 81595999990 in words is "eighty-one billion, five hundred ninety-five million, nine hundred ninety-nine thousand, nine hundred ninety".