406866856 has 24 divisors (see below), whose sum is σ = 838534410. Its totient is φ = 184939040.

The previous prime is 406866853. The next prime is 406866857. The reversal of 406866856 is 658668604.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 396408100 + 10458756 = 19910^2 + 3234^2 .

It is a super-2 number, since 2×406866856² = 331081277022649472, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (406866851) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 209191 + ... + 211126.

Almost surely, 2^406866856 is an apocalyptic number.

It is an amenable number.

406866856 is an abundant number, since it is smaller than the sum of its proper divisors (431667554).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

406866856 is a wasteful number, since it uses less digits than its factorization.

406866856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420345 (or 420330 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 49.

The square root of 406866856 is about 20170.9408803853. The cubic root of 406866856 is about 740.9986856804.

The spelling of 406866856 in words is "four hundred six million, eight hundred sixty-six thousand, eight hundred fifty-six".