646377 has 4 divisors (see below), whose sum is σ = 861840. Its totient is φ = 430916.

The previous prime is 646339. The next prime is 646379. The reversal of 646377 is 773646.

646377 is nontrivially palindromic in base 15.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 646377 - 2¹⁰ = 645353 is a prime.

It is a super-2 number, since 2×646377² = 835606452258, which contains 22 as substring.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (646379) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107727 + ... + 107732.

It is an arithmetic number, because the mean of its divisors is an integer number (215460).

2⁶⁴⁶³⁷⁷ is an apocalyptic number.

It is an amenable number.

646377 is a deficient number, since it is larger than the sum of its proper divisors (215463).

646377 is a wasteful number, since it uses less digits than its factorization.

646377 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215462.

The product of its digits is 21168, while the sum is 33.

The square root of 646377 is about 803.9757459028. The cubic root of 646377 is about 86.4626677977.

It can be divided in two parts, 64 and 6377, that added together give a triangular number (6441 = T₁₁₃).

The spelling of 646377 in words is "six hundred forty-six thousand, three hundred seventy-seven".