81377692 has 12 divisors (see below), whose sum is σ = 155357496. Its totient is φ = 36989840.

The previous prime is 81377687. The next prime is 81377701. The reversal of 81377692 is 29677318.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 924703 + ... + 924790.

It is an arithmetic number, because the mean of its divisors is an integer number (12946458).

Almost surely, 2^81377692 is an apocalyptic number.

It is an amenable number.

81377692 is a deficient number, since it is larger than the sum of its proper divisors (73979804).

81377692 is a wasteful number, since it uses less digits than its factorization.

81377692 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1849508 (or 1849506 counting only the distinct ones).

The product of its digits is 127008, while the sum is 43.

The square root of 81377692 is about 9020.9584856599. The cubic root of 81377692 is about 433.3463299192.

It can be divided in two parts, 81 and 377692, that added together give a palindrome (377773).

The spelling of 81377692 in words is "eighty-one million, three hundred seventy-seven thousand, six hundred ninety-two".