668964929 has 2 divisors, whose sum is σ = 668964930. Its totient is φ = 668964928.

The previous prime is 668964871. The next prime is 668964931. The reversal of 668964929 is 929469866.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 610090000 + 58874929 = 24700^2 + 7673^2 .

It is a cyclic number.

It is not a de Polignac number, because 668964929 - 2¹⁶ = 668899393 is a prime.

Together with 668964931, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (668964529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334482464 + 334482465.

It is an arithmetic number, because the mean of its divisors is an integer number (334482465).

Almost surely, 2^668964929 is an apocalyptic number.

It is an amenable number.

668964929 is a deficient number, since it is larger than the sum of its proper divisors (1).

668964929 is an equidigital number, since it uses as much as digits as its factorization.

668964929 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10077696, while the sum is 59.

The square root of 668964929 is about 25864.3563422715. The cubic root of 668964929 is about 874.5831719140.

The spelling of 668964929 in words is "six hundred sixty-eight million, nine hundred sixty-four thousand, nine hundred twenty-nine".