866408431 has 4 divisors (see below), whose sum is σ = 990181072. Its totient is φ = 742635792.

The previous prime is 866408399. The next prime is 866408443. The reversal of 866408431 is 134804668.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 866408431 - 2⁵ = 866408399 is a prime.

It is a super-2 number, since 2×866408431² = 1501327138615763522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866402431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61886310 + ... + 61886323.

It is an arithmetic number, because the mean of its divisors is an integer number (247545268).

Almost surely, 2^866408431 is an apocalyptic number.

866408431 is a deficient number, since it is larger than the sum of its proper divisors (123772641).

866408431 is a wasteful number, since it uses less digits than its factorization.

866408431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123772640.

The product of its (nonzero) digits is 110592, while the sum is 40.

The square root of 866408431 is about 29434.8166462779. The cubic root of 866408431 is about 953.3247976181.

The spelling of 866408431 in words is "eight hundred sixty-six million, four hundred eight thousand, four hundred thirty-one".