857261081 has 2 divisors, whose sum is σ = 857261082. Its totient is φ = 857261080.

The previous prime is 857261003. The next prime is 857261089. The reversal of 857261081 is 180162758.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 493062025 + 364199056 = 22205^2 + 19084^2 .

It is a cyclic number.

It is not a de Polignac number, because 857261081 - 2¹⁰ = 857260057 is a prime.

It is a super-2 number, since 2×857261081² = 1469793121994577122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (857261089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428630540 + 428630541.

It is an arithmetic number, because the mean of its divisors is an integer number (428630541).

Almost surely, 2^857261081 is an apocalyptic number.

It is an amenable number.

857261081 is a deficient number, since it is larger than the sum of its proper divisors (1).

857261081 is an equidigital number, since it uses as much as digits as its factorization.

857261081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26880, while the sum is 38.

The square root of 857261081 is about 29279.0211755789. The cubic root of 857261081 is about 949.9579227901.

The spelling of 857261081 in words is "eight hundred fifty-seven million, two hundred sixty-one thousand, eighty-one".