646412657 has 4 divisors (see below), whose sum is σ = 705177456. Its totient is φ = 587647860.

The previous prime is 646412621. The next prime is 646412687. The reversal of 646412657 is 756214646.

It is a happy number.

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 646412657 - 2¹⁸ = 646150513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646412617) 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, 29382383 + ... + 29382404.

It is an arithmetic number, because the mean of its divisors is an integer number (176294364).

Almost surely, 2^646412657 is an apocalyptic number.

It is an amenable number.

646412657 is a deficient number, since it is larger than the sum of its proper divisors (58764799).

646412657 is a wasteful number, since it uses less digits than its factorization.

646412657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58764798.

The product of its digits is 241920, while the sum is 41.

The square root of 646412657 is about 25424.6466445455. The cubic root of 646412657 is about 864.6425765558.

The spelling of 646412657 in words is "six hundred forty-six million, four hundred twelve thousand, six hundred fifty-seven".