20617620 has 24 divisors (see below), whose sum is σ = 57729504. Its totient is φ = 5498016.

The previous prime is 20617607. The next prime is 20617627. The reversal of 20617620 is 2671602.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20617627) 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, 171754 + ... + 171873.

It is an arithmetic number, because the mean of its divisors is an integer number (2405396).

Almost surely, 2^20617620 is an apocalyptic number.

20617620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20617620 is an abundant number, since it is smaller than the sum of its proper divisors (37111884).

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

20617620 is a wasteful number, since it uses less digits than its factorization.

20617620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343639 (or 343637 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 20617620 is about 4540.6629471917. The cubic root of 20617620 is about 274.2076143277.

The spelling of 20617620 in words is "twenty million, six hundred seventeen thousand, six hundred twenty".