79881819 has 8 divisors (see below), whose sum is σ = 106677312. Its totient is φ = 53170440.

The previous prime is 79881799. The next prime is 79881821. The reversal of 79881819 is 91818897.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 79881819 - 2¹² = 79877723 is a prime.

It is a super-2 number, since 2×79881819² = 12762210013497522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (79881839) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18777 + ... + 22634.

It is an arithmetic number, because the mean of its divisors is an integer number (13334664).

Almost surely, 2^79881819 is an apocalyptic number.

79881819 is a deficient number, since it is larger than the sum of its proper divisors (26795493).

79881819 is a wasteful number, since it uses less digits than its factorization.

79881819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42057.

The product of its digits is 290304, while the sum is 51.

The square root of 79881819 is about 8937.6629495635. The cubic root of 79881819 is about 430.6746557347.

The spelling of 79881819 in words is "seventy-nine million, eight hundred eighty-one thousand, eight hundred nineteen".