8990864921 has 2 divisors, whose sum is σ = 8990864922. Its totient is φ = 8990864920.

The previous prime is 8990864917. The next prime is 8990864941. The reversal of 8990864921 is 1294680998.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6024864400 + 2966000521 = 77620^2 + 54461^2 .

It is a cyclic number.

It is not a de Polignac number, because 8990864921 - 2² = 8990864917 is a prime.

It is not a weakly prime, because it can be changed into another prime (8990864941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4495432460 + 4495432461.

It is an arithmetic number, because the mean of its divisors is an integer number (4495432461).

Almost surely, 2^8990864921 is an apocalyptic number.

It is an amenable number.

8990864921 is a deficient number, since it is larger than the sum of its proper divisors (1).

8990864921 is an equidigital number, since it uses as much as digits as its factorization.

8990864921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2239488, while the sum is 56.

The square root of 8990864921 is about 94820.1714879276. The cubic root of 8990864921 is about 2079.3798170277.

The spelling of 8990864921 in words is "eight billion, nine hundred ninety million, eight hundred sixty-four thousand, nine hundred twenty-one".