108439921 has 4 divisors (see below), whose sum is σ = 108499572. Its totient is φ = 108380272.

The previous prime is 108439913. The next prime is 108439931. The reversal of 108439921 is 129934801.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 27709696 + 80730225 = 5264^2 + 8985^2 .

It is a cyclic number.

It is not a de Polignac number, because 108439921 - 2³ = 108439913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (108439901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27010 + ... + 30763.

It is an arithmetic number, because the mean of its divisors is an integer number (27124893).

Almost surely, 2^108439921 is an apocalyptic number.

It is an amenable number.

108439921 is a deficient number, since it is larger than the sum of its proper divisors (59651).

108439921 is an equidigital number, since it uses as much as digits as its factorization.

108439921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59650.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 108439921 is about 10413.4490443849. The cubic root of 108439921 is about 476.8660424585.

The spelling of 108439921 in words is "one hundred eight million, four hundred thirty-nine thousand, nine hundred twenty-one".