402857681 has 8 divisors (see below), whose sum is σ = 408602880. Its totient is φ = 397133872.

The previous prime is 402857629. The next prime is 402857701. The reversal of 402857681 is 186758204.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 402857681 - 2¹⁸ = 402595537 is a prime.

It is a super-2 number, since 2×402857681² = 324588622281395522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (402857281) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34691 + ... + 44823.

It is an arithmetic number, because the mean of its divisors is an integer number (51075360).

Almost surely, 2^402857681 is an apocalyptic number.

It is an amenable number.

402857681 is a deficient number, since it is larger than the sum of its proper divisors (5745199).

402857681 is a wasteful number, since it uses less digits than its factorization.

402857681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10695.

The product of its (nonzero) digits is 107520, while the sum is 41.

The square root of 402857681 is about 20071.3148796983. The cubic root of 402857681 is about 738.5567688900.

The spelling of 402857681 in words is "four hundred two million, eight hundred fifty-seven thousand, six hundred eighty-one".