644610662 has 4 divisors (see below), whose sum is σ = 966915996. Its totient is φ = 322305330.

The previous prime is 644610661. The next prime is 644610671. The reversal of 644610662 is 266016446.

644610662 is nontrivially palindromic in base 4.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644610661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161152664 + ... + 161152667.

It is an arithmetic number, because the mean of its divisors is an integer number (241728999).

Almost surely, 2^644610662 is an apocalyptic number.

644610662 is a deficient number, since it is larger than the sum of its proper divisors (322305334).

644610662 is a wasteful number, since it uses less digits than its factorization.

644610662 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322305333.

The product of its (nonzero) digits is 41472, while the sum is 35.

The square root of 644610662 is about 25389.1839569530. The cubic root of 644610662 is about 863.8383783691.

The spelling of 644610662 in words is "six hundred forty-four million, six hundred ten thousand, six hundred sixty-two".