120805639 has 4 divisors (see below), whose sum is σ = 123752160. Its totient is φ = 117859120.

The previous prime is 120805609. The next prime is 120805649. The reversal of 120805639 is 936508021.

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

It is a cyclic number.

It is not a de Polignac number, because 120805639 - 2⁹ = 120805127 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 (120805609) 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, 1473199 + ... + 1473280.

It is an arithmetic number, because the mean of its divisors is an integer number (30938040).

Almost surely, 2^120805639 is an apocalyptic number.

120805639 is a deficient number, since it is larger than the sum of its proper divisors (2946521).

120805639 is an equidigital number, since it uses as much as digits as its factorization.

120805639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2946520.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 120805639 is about 10991.1618585116. The cubic root of 120805639 is about 494.3437741639.

The spelling of 120805639 in words is "one hundred twenty million, eight hundred five thousand, six hundred thirty-nine".