644467 has 8 divisors (see below), whose sum is σ = 678240. Its totient is φ = 611520.

The previous prime is 644447. The next prime is 644489. The reversal of 644467 is 764446.

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

It is a cyclic number.

It is not a de Polignac number, because 644467 - 2¹¹ = 642419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (644447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1903 + ... + 2215.

It is an arithmetic number, because the mean of its divisors is an integer number (84780).

2⁶⁴⁴⁴⁶⁷ is an apocalyptic number.

644467 is a deficient number, since it is larger than the sum of its proper divisors (33773).

644467 is a wasteful number, since it uses less digits than its factorization.

644467 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413.

The product of its digits is 16128, while the sum is 31.

The square root of 644467 is about 802.7870203236. The cubic root of 644467 is about 86.3774200110.

It can be divided in two parts, 644 and 467, that added together give a palindrome (1111).

The spelling of 644467 in words is "six hundred forty-four thousand, four hundred sixty-seven".