646677943 has 8 divisors (see below), whose sum is σ = 685914912. Its totient is φ = 607574016.

The previous prime is 646677929. The next prime is 646677961. The reversal of 646677943 is 349776646.

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

It is not a de Polignac number, because 646677943 - 2¹⁷ = 646546871 is a prime.

It is a super-2 number, since 2×646677943² = 836384723925422498, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646677743) 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, 23155 + ... + 42772.

It is an arithmetic number, because the mean of its divisors is an integer number (85739364).

Almost surely, 2^646677943 is an apocalyptic number.

646677943 is a deficient number, since it is larger than the sum of its proper divisors (39236969).

646677943 is a wasteful number, since it uses less digits than its factorization.

646677943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66521.

The product of its digits is 4572288, while the sum is 52.

The square root of 646677943 is about 25429.8632123730. The cubic root of 646677943 is about 864.7608427008.

The spelling of 646677943 in words is "six hundred forty-six million, six hundred seventy-seven thousand, nine hundred forty-three".