679945421 has 2 divisors, whose sum is σ = 679945422. Its totient is φ = 679945420.

The previous prime is 679945417. The next prime is 679945477. The reversal of 679945421 is 124549976.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 366301321 + 313644100 = 19139^2 + 17710^2 .

It is a cyclic number.

It is not a de Polignac number, because 679945421 - 2² = 679945417 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (679945121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339972710 + 339972711.

It is an arithmetic number, because the mean of its divisors is an integer number (339972711).

Almost surely, 2^679945421 is an apocalyptic number.

It is an amenable number.

679945421 is a deficient number, since it is larger than the sum of its proper divisors (1).

679945421 is an equidigital number, since it uses as much as digits as its factorization.

679945421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 47.

The square root of 679945421 is about 26075.7630952576. The cubic root of 679945421 is about 879.3424068839.

The spelling of 679945421 in words is "six hundred seventy-nine million, nine hundred forty-five thousand, four hundred twenty-one".