20975660 has 12 divisors (see below), whose sum is σ = 44048928. Its totient is φ = 8390256.

The previous prime is 20975657. The next prime is 20975663. The reversal of 20975660 is 6657902.

It is an interprime number because it is at equal distance from previous prime (20975657) and next prime (20975663).

It is a self number, because there is not a number n which added to its sum of digits gives 20975660.

It is not an unprimeable number, because it can be changed into a prime (20975663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 524372 + ... + 524411.

It is an arithmetic number, because the mean of its divisors is an integer number (3670744).

Almost surely, 2^20975660 is an apocalyptic number.

20975660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20975660 is an abundant number, since it is smaller than the sum of its proper divisors (23073268).

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

20975660 is a wasteful number, since it uses less digits than its factorization.

20975660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1048792 (or 1048790 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 35.

The square root of 20975660 is about 4579.9192132613. The cubic root of 20975660 is about 275.7857856137.

The spelling of 20975660 in words is "twenty million, nine hundred seventy-five thousand, six hundred sixty".