625989 has 16 divisors (see below), whose sum is σ = 1027712. Its totient is φ = 330048.

The previous prime is 625979. The next prime is 625997. The reversal of 625989 is 989526.

It is a happy number.

It is not a de Polignac number, because 625989 - 2⁷ = 625861 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an Ulam number.

625989 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (625909) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 874 + ... + 1419.

It is an arithmetic number, because the mean of its divisors is an integer number (64232).

2⁶²⁵⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

625989 is a deficient number, since it is larger than the sum of its proper divisors (401723).

625989 is a wasteful number, since it uses less digits than its factorization.

625989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2316.

The product of its digits is 38880, while the sum is 39.

The square root of 625989 is about 791.1946663116. The cubic root of 625989 is about 85.5438713328.

The spelling of 625989 in words is "six hundred twenty-five thousand, nine hundred eighty-nine".