84879919 has 2 divisors, whose sum is σ = 84879920. Its totient is φ = 84879918.

The previous prime is 84879863. The next prime is 84879967. The reversal of 84879919 is 91997848.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 84879919 - 2²⁵ = 51325487 is a prime.

It is a super-2 number, since 2×84879919² = 14409201298893122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 84879919.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84879989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42439959 + 42439960.

It is an arithmetic number, because the mean of its divisors is an integer number (42439960).

Almost surely, 2^84879919 is an apocalyptic number.

84879919 is a deficient number, since it is larger than the sum of its proper divisors (1).

84879919 is an equidigital number, since it uses as much as digits as its factorization.

84879919 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1306368, while the sum is 55.

The square root of 84879919 is about 9213.0298490779. The cubic root of 84879919 is about 439.4758203429.

The spelling of 84879919 in words is "eighty-four million, eight hundred seventy-nine thousand, nine hundred nineteen".