6393926221 has 2 divisors, whose sum is σ = 6393926222. Its totient is φ = 6393926220.

The previous prime is 6393926171. The next prime is 6393926299. The reversal of 6393926221 is 1226293936.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5186016196 + 1207910025 = 72014^2 + 34755^2 .

It is a cyclic number.

It is not a de Polignac number, because 6393926221 - 2⁷ = 6393926093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6393926521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3196963110 + 3196963111.

It is an arithmetic number, because the mean of its divisors is an integer number (3196963111).

Almost surely, 2^6393926221 is an apocalyptic number.

It is an amenable number.

6393926221 is a deficient number, since it is larger than the sum of its proper divisors (1).

6393926221 is an equidigital number, since it uses as much as digits as its factorization.

6393926221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 209952, while the sum is 43.

The square root of 6393926221 is about 79962.0298704329. The cubic root of 6393926221 is about 1856.0480145323.

The spelling of 6393926221 in words is "six billion, three hundred ninety-three million, nine hundred twenty-six thousand, two hundred twenty-one".