839542921 has 8 divisors (see below), whose sum is σ = 979059200. Its totient is φ = 719607924.

The previous prime is 839542871. The next prime is 839542927. The reversal of 839542921 is 129245938.

It is not a de Polignac number, because 839542921 - 2⁹ = 839542409 is a prime.

It is not an unprimeable number, because it can be changed into a prime (839542927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1223481 + ... + 1224166.

It is an arithmetic number, because the mean of its divisors is an integer number (122382400).

Almost surely, 2^839542921 is an apocalyptic number.

It is an amenable number.

839542921 is a deficient number, since it is larger than the sum of its proper divisors (139516279).

839542921 is an equidigital number, since it uses as much as digits as its factorization.

839542921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2447668 (or 2447654 counting only the distinct ones).

The product of its digits is 155520, while the sum is 43.

The square root of 839542921 is about 28974.8670575035. The cubic root of 839542921 is about 943.3676254215.

The spelling of 839542921 in words is "eight hundred thirty-nine million, five hundred forty-two thousand, nine hundred twenty-one".