646190477 has 4 divisors (see below), whose sum is σ = 652118940. Its totient is φ = 640262016.

The previous prime is 646190471. The next prime is 646190521. The reversal of 646190477 is 774091646.

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

It can be written as a sum of positive squares in 2 ways, for example, as 219602761 + 426587716 = 14819^2 + 20654^2 .

It is a cyclic number.

It is not a de Polignac number, because 646190477 - 2²⁰ = 645141901 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646190471) 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, 2964068 + ... + 2964285.

It is an arithmetic number, because the mean of its divisors is an integer number (163029735).

Almost surely, 2^646190477 is an apocalyptic number.

It is an amenable number.

646190477 is a deficient number, since it is larger than the sum of its proper divisors (5928463).

646190477 is a wasteful number, since it uses less digits than its factorization.

646190477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5928462.

The product of its (nonzero) digits is 254016, while the sum is 44.

The square root of 646190477 is about 25420.2768867690. The cubic root of 646190477 is about 864.5435024326.

The spelling of 646190477 in words is "six hundred forty-six million, one hundred ninety thousand, four hundred seventy-seven".