989636761 has 2 divisors, whose sum is σ = 989636762. Its totient is φ = 989636760.

The previous prime is 989636731. The next prime is 989636779. The reversal of 989636761 is 167636989.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 495908361 + 493728400 = 22269^2 + 22220^2 .

It is a cyclic number.

It is not a de Polignac number, because 989636761 - 2⁵ = 989636729 is a prime.

It is a super-2 number, since 2×989636761² = 1958761837445142242, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not a weakly prime, because it can be changed into another prime (989636731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494818380 + 494818381.

It is an arithmetic number, because the mean of its divisors is an integer number (494818381).

Almost surely, 2^989636761 is an apocalyptic number.

It is an amenable number.

989636761 is a deficient number, since it is larger than the sum of its proper divisors (1).

989636761 is an equidigital number, since it uses as much as digits as its factorization.

989636761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2939328, while the sum is 55.

The square root of 989636761 is about 31458.4926689122. The cubic root of 989636761 is about 996.5335848502.

The spelling of 989636761 in words is "nine hundred eighty-nine million, six hundred thirty-six thousand, seven hundred sixty-one".