19918839 has 16 divisors (see below), whose sum is σ = 27493760. Its totient is φ = 12817440.

The previous prime is 19918753. The next prime is 19918901. The reversal of 19918839 is 93881991.

It is not a de Polignac number, because 19918839 - 2⁷ = 19918711 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19918039) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14784 + ... + 16074.

It is an arithmetic number, because the mean of its divisors is an integer number (1718360).

Almost surely, 2^19918839 is an apocalyptic number.

19918839 is a deficient number, since it is larger than the sum of its proper divisors (7574921).

19918839 is a wasteful number, since it uses less digits than its factorization.

19918839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1470.

The product of its digits is 139968, while the sum is 48.

The square root of 19918839 is about 4463.0526548541. The cubic root of 19918839 is about 271.0740891186.

The spelling of 19918839 in words is "nineteen million, nine hundred eighteen thousand, eight hundred thirty-nine".