644653462 has 4 divisors (see below), whose sum is σ = 966980196. Its totient is φ = 322326730.

The previous prime is 644653423. The next prime is 644653487. The reversal of 644653462 is 264356446.

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

It is a super-4 number, since 4×644653462⁴ (a number of 36 digits) contains 4444 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161163364 + ... + 161163367.

It is an arithmetic number, because the mean of its divisors is an integer number (241745049).

Almost surely, 2^644653462 is an apocalyptic number.

644653462 is a deficient number, since it is larger than the sum of its proper divisors (322326734).

644653462 is a wasteful number, since it uses less digits than its factorization.

644653462 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322326733.

The product of its digits is 414720, while the sum is 40.

The square root of 644653462 is about 25390.0268215691. The cubic root of 644653462 is about 863.8574966093.

The spelling of 644653462 in words is "six hundred forty-four million, six hundred fifty-three thousand, four hundred sixty-two".