857390641 has 2 divisors, whose sum is σ = 857390642. Its totient is φ = 857390640.

The previous prime is 857390629. The next prime is 857390669. The reversal of 857390641 is 146093758.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 829670416 + 27720225 = 28804^2 + 5265^2 .

It is a cyclic number.

It is not a de Polignac number, because 857390641 - 2⁵ = 857390609 is a prime.

It is a super-2 number, since 2×857390641² = 1470237422548781762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (857390671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428695320 + 428695321.

It is an arithmetic number, because the mean of its divisors is an integer number (428695321).

Almost surely, 2^857390641 is an apocalyptic number.

It is an amenable number.

857390641 is a deficient number, since it is larger than the sum of its proper divisors (1).

857390641 is an equidigital number, since it uses as much as digits as its factorization.

857390641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 43.

The square root of 857390641 is about 29281.2335976475. The cubic root of 857390641 is about 950.0057768808.

The spelling of 857390641 in words is "eight hundred fifty-seven million, three hundred ninety thousand, six hundred forty-one".