81892637786 has 16 divisors (see below), whose sum is σ = 123329139840. Its totient is φ = 40783186080.

The previous prime is 81892637773. The next prime is 81892637791. The reversal of 81892637786 is 68773629818.

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, 567470 + ... + 696998.

It is an arithmetic number, because the mean of its divisors is an integer number (7708071240).

Almost surely, 2^81892637786 is an apocalyptic number.

81892637786 is a deficient number, since it is larger than the sum of its proper divisors (41436502054).

81892637786 is a wasteful number, since it uses less digits than its factorization.

81892637786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130789.

The product of its digits is 48771072, while the sum is 65.

The spelling of 81892637786 in words is "eighty-one billion, eight hundred ninety-two million, six hundred thirty-seven thousand, seven hundred eighty-six".