620644 has 6 divisors (see below), whose sum is σ = 1086134. Its totient is φ = 310320.

The previous prime is 620639. The next prime is 620647. The reversal of 620644 is 446026.

It can be written as a sum of positive squares in only one way, i.e., 580644 + 40000 = 762^2 + 200^2 .

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (620647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77577 + ... + 77584.

2⁶²⁰⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

620644 is a deficient number, since it is larger than the sum of its proper divisors (465490).

620644 is a wasteful number, since it uses less digits than its factorization.

620644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155165 (or 155163 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 620644 is about 787.8096216726. The cubic root of 620644 is about 85.2997032737.

The spelling of 620644 in words is "six hundred twenty thousand, six hundred forty-four".