81792279 has 6 divisors (see below), whose sum is σ = 118144416. Its totient is φ = 54528180.

The previous prime is 81792257. The next prime is 81792281. The reversal of 81792279 is 97229718.

It is not a de Polignac number, because 81792279 - 2⁹ = 81791767 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81792239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4544007 + ... + 4544024.

It is an arithmetic number, because the mean of its divisors is an integer number (19690736).

Almost surely, 2^81792279 is an apocalyptic number.

81792279 is a deficient number, since it is larger than the sum of its proper divisors (36352137).

81792279 is a wasteful number, since it uses less digits than its factorization.

81792279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9088037 (or 9088034 counting only the distinct ones).

The product of its digits is 127008, while the sum is 45.

The square root of 81792279 is about 9043.9083918403. The cubic root of 81792279 is about 434.0809928337.

It can be divided in two parts, 817 and 92279, that added together give a triangular number (93096 = T₄₃₁).

The spelling of 81792279 in words is "eighty-one million, seven hundred ninety-two thousand, two hundred seventy-nine".