990078839 has 2 divisors, whose sum is σ = 990078840. Its totient is φ = 990078838.

The previous prime is 990078781. The next prime is 990078841. The reversal of 990078839 is 938870099.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 990078839 - 2²⁸ = 721643383 is a prime.

It is a super-2 number, since 2×990078839² = 1960512214871175842, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 990078841, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (990071839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495039419 + 495039420.

It is an arithmetic number, because the mean of its divisors is an integer number (495039420).

Almost surely, 2^990078839 is an apocalyptic number.

990078839 is a deficient number, since it is larger than the sum of its proper divisors (1).

990078839 is an equidigital number, since it uses as much as digits as its factorization.

990078839 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 979776, while the sum is 53.

The square root of 990078839 is about 31465.5182541143. The cubic root of 990078839 is about 996.6819490479.

The spelling of 990078839 in words is "nine hundred ninety million, seventy-eight thousand, eight hundred thirty-nine".