669984901 has 2 divisors, whose sum is σ = 669984902. Its totient is φ = 669984900.

The previous prime is 669984869. The next prime is 669984911. The reversal of 669984901 is 109489966.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 400040001 + 269944900 = 20001^2 + 16430^2 .

It is a cyclic number.

It is not a de Polignac number, because 669984901 - 2⁵ = 669984869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (669984911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334992450 + 334992451.

It is an arithmetic number, because the mean of its divisors is an integer number (334992451).

Almost surely, 2^669984901 is an apocalyptic number.

It is an amenable number.

669984901 is a deficient number, since it is larger than the sum of its proper divisors (1).

669984901 is an equidigital number, since it uses as much as digits as its factorization.

669984901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 839808, while the sum is 52.

The square root of 669984901 is about 25884.0665468160. The cubic root of 669984901 is about 875.0274390307.

The spelling of 669984901 in words is "six hundred sixty-nine million, nine hundred eighty-four thousand, nine hundred one".