989708639 has 2 divisors, whose sum is σ = 989708640. Its totient is φ = 989708638.

The previous prime is 989708627. The next prime is 989708647. The reversal of 989708639 is 936807989.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 989708639 - 2⁴ = 989708623 is a prime.

It is a super-2 number, since 2×989708639² = 1959046380222464642, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (989708609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494854319 + 494854320.

It is an arithmetic number, because the mean of its divisors is an integer number (494854320).

Almost surely, 2^989708639 is an apocalyptic number.

989708639 is a deficient number, since it is larger than the sum of its proper divisors (1).

989708639 is an equidigital number, since it uses as much as digits as its factorization.

989708639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5878656, while the sum is 59.

The square root of 989708639 is about 31459.6350741708. The cubic root of 989708639 is about 996.5577105731.

The spelling of 989708639 in words is "nine hundred eighty-nine million, seven hundred eight thousand, six hundred thirty-nine".