989878651 has 2 divisors, whose sum is σ = 989878652. Its totient is φ = 989878650.

The previous prime is 989878633. The next prime is 989878661. The reversal of 989878651 is 156878989.

989878651 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is an emirp because it is prime and its reverse (156878989) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 989878651 - 2⁷ = 989878523 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 989878651.

It is not a weakly prime, because it can be changed into another prime (989878661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494939325 + 494939326.

It is an arithmetic number, because the mean of its divisors is an integer number (494939326).

Almost surely, 2^989878651 is an apocalyptic number.

989878651 is a deficient number, since it is larger than the sum of its proper divisors (1).

989878651 is an equidigital number, since it uses as much as digits as its factorization.

989878651 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8709120, while the sum is 61.

The square root of 989878651 is about 31462.3370238131. The cubic root of 989878651 is about 996.6147701502.

The spelling of 989878651 in words is "nine hundred eighty-nine million, eight hundred seventy-eight thousand, six hundred fifty-one".