620644653 has 16 divisors (see below), whose sum is σ = 973560960. Its totient is φ = 389423808.

The previous prime is 620644639. The next prime is 620644669. The reversal of 620644653 is 356446026.

620644653 is a `hidden beast` number, since 6 + 2 + 0 + 644 + 6 + 5 + 3 = 666.

It is not a de Polignac number, because 620644653 - 2⁵ = 620644621 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a zygodrome in base 8.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (620644603) 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, 675625 + ... + 676542.

It is an arithmetic number, because the mean of its divisors is an integer number (60847560).

Almost surely, 2^620644653 is an apocalyptic number.

It is an amenable number.

620644653 is a deficient number, since it is larger than the sum of its proper divisors (352916307).

620644653 is a wasteful number, since it uses less digits than its factorization.

620644653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1352193 (or 1352187 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 36.

The square root of 620644653 is about 24912.7407765585. The cubic root of 620644653 is about 852.9973318920.

The spelling of 620644653 in words is "six hundred twenty million, six hundred forty-four thousand, six hundred fifty-three".