81376992 has 36 divisors (see below), whose sum is σ = 231416640. Its totient is φ = 27125568.

The previous prime is 81376979. The next prime is 81376993. The reversal of 81376992 is 29967318.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81376993) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 140992 + ... + 141567.

It is an arithmetic number, because the mean of its divisors is an integer number (6428240).

Almost surely, 2^81376992 is an apocalyptic number.

It is an amenable number.

81376992 is an abundant number, since it is smaller than the sum of its proper divisors (150039648).

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

81376992 is a wasteful number, since it uses less digits than its factorization.

81376992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282575 (or 282564 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 81376992 is about 9020.9196870386. The cubic root of 81376992 is about 433.3450873866.

It can be divided in two parts, 8137 and 6992, that added together give a square (15129 = 123²).

The spelling of 81376992 in words is "eighty-one million, three hundred seventy-six thousand, nine hundred ninety-two".