631609 has 8 divisors (see below), whose sum is σ = 700128. Its totient is φ = 564960.

The previous prime is 631597. The next prime is 631613. The reversal of 631609 is 906136.

631609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 631609 - 2⁵ = 631577 is a prime.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (631619) 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, 309 + ... + 1165.

It is an arithmetic number, because the mean of its divisors is an integer number (87516).

2⁶³¹⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

631609 is a deficient number, since it is larger than the sum of its proper divisors (68519).

631609 is a wasteful number, since it uses less digits than its factorization.

631609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 935.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 631609 is about 794.7383217135. The cubic root of 631609 is about 85.7991074360.

The spelling of 631609 in words is "six hundred thirty-one thousand, six hundred nine".