646563253 has 4 divisors (see below), whose sum is σ = 738929440. Its totient is φ = 554197068.

The previous prime is 646563221. The next prime is 646563319. The reversal of 646563253 is 352365646.

646563253 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 646563253 - 2⁵ = 646563221 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 (646563053) 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, 46183083 + ... + 46183096.

It is an arithmetic number, because the mean of its divisors is an integer number (184732360).

Almost surely, 2^646563253 is an apocalyptic number.

It is an amenable number.

646563253 is a deficient number, since it is larger than the sum of its proper divisors (92366187).

646563253 is an equidigital number, since it uses as much as digits as its factorization.

646563253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92366186.

The product of its digits is 388800, while the sum is 40.

The square root of 646563253 is about 25427.6080864874. The cubic root of 646563253 is about 864.7097171568.

The spelling of 646563253 in words is "six hundred forty-six million, five hundred sixty-three thousand, two hundred fifty-three".