396921257 has 2 divisors, whose sum is σ = 396921258. Its totient is φ = 396921256.

The previous prime is 396921233. The next prime is 396921299. The reversal of 396921257 is 752129693.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 213481321 + 183439936 = 14611^2 + 13544^2 .

It is a cyclic number.

It is not a de Polignac number, because 396921257 - 2¹² = 396917161 is a prime.

It is not a weakly prime, because it can be changed into another prime (396921227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198460628 + 198460629.

It is an arithmetic number, because the mean of its divisors is an integer number (198460629).

Almost surely, 2^396921257 is an apocalyptic number.

It is an amenable number.

396921257 is a deficient number, since it is larger than the sum of its proper divisors (1).

396921257 is an equidigital number, since it uses as much as digits as its factorization.

396921257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 204120, while the sum is 44.

The square root of 396921257 is about 19922.8827482370. The cubic root of 396921257 is about 734.9110645627.

It can be divided in two parts, 39 and 6921257, that added together give a palindrome (6921296).

The spelling of 396921257 in words is "three hundred ninety-six million, nine hundred twenty-one thousand, two hundred fifty-seven".