644363446 has 8 divisors (see below), whose sum is σ = 1008568944. Its totient is φ = 308173800.

The previous prime is 644363443. The next prime is 644363449.

It is a happy number.

644363446 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (644363443) and next prime (644363449).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 644363399 and 644363408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644363443) 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, 7003905 + ... + 7003996.

It is an arithmetic number, because the mean of its divisors is an integer number (126071118).

Almost surely, 2^644363446 is an apocalyptic number.

644363446 is a deficient number, since it is larger than the sum of its proper divisors (364205498).

644363446 is a wasteful number, since it uses less digits than its factorization.

644363446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14007926.

The product of its digits is 497664, while the sum is 40.

The square root of 644363446 is about 25384.3149602269. The cubic root of 644363446 is about 863.7279334204.

It can be divided in two parts, 644363 and 446, that added together give a square (644809 = 803²).

The spelling of 644363446 in words is "six hundred forty-four million, three hundred sixty-three thousand, four hundred forty-six".