121398839 has 2 divisors, whose sum is σ = 121398840. Its totient is φ = 121398838.

The previous prime is 121398817. The next prime is 121398857. The reversal of 121398839 is 938893121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 121398839 - 2⁸ = 121398583 is a prime.

It is a super-2 number, since 2×121398839² = 29475356221095842, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121398839.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121398889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60699419 + 60699420.

It is an arithmetic number, because the mean of its divisors is an integer number (60699420).

Almost surely, 2^121398839 is an apocalyptic number.

121398839 is a deficient number, since it is larger than the sum of its proper divisors (1).

121398839 is an equidigital number, since it uses as much as digits as its factorization.

121398839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 93312, while the sum is 44.

The square root of 121398839 is about 11018.1141308302. The cubic root of 121398839 is about 495.1515897997.

The spelling of 121398839 in words is "one hundred twenty-one million, three hundred ninety-eight thousand, eight hundred thirty-nine".