631664 has 40 divisors (see below), whose sum is σ = 1385328. Its totient is φ = 276480.

The previous prime is 631643. The next prime is 631667. The reversal of 631664 is 466136.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631667) 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, 6464 + ... + 6560.

2⁶³¹⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 631664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (692664).

631664 is an abundant number, since it is smaller than the sum of its proper divisors (753664).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

631664 is a wasteful number, since it uses less digits than its factorization.

631664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153 (or 147 counting only the distinct ones).

The product of its digits is 2592, while the sum is 26.

The square root of 631664 is about 794.7729235448. The cubic root of 631664 is about 85.8015978026.

The spelling of 631664 in words is "six hundred thirty-one thousand, six hundred sixty-four".