394968521 has 2 divisors, whose sum is σ = 394968522. Its totient is φ = 394968520.

The previous prime is 394968499. The next prime is 394968533. The reversal of 394968521 is 125869493.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 289680400 + 105288121 = 17020^2 + 10261^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-394968521 is a prime.

It is not a weakly prime, because it can be changed into another prime (394968421) 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, 197484260 + 197484261.

It is an arithmetic number, because the mean of its divisors is an integer number (197484261).

Almost surely, 2^394968521 is an apocalyptic number.

It is an amenable number.

394968521 is a deficient number, since it is larger than the sum of its proper divisors (1).

394968521 is an equidigital number, since it uses as much as digits as its factorization.

394968521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 466560, while the sum is 47.

The square root of 394968521 is about 19873.8149583818. The cubic root of 394968521 is about 733.7039005696.

The spelling of 394968521 in words is "three hundred ninety-four million, nine hundred sixty-eight thousand, five hundred twenty-one".