20660880 has 80 divisors (see below), whose sum is σ = 66138624. Its totient is φ = 5329920.

The previous prime is 20660879. The next prime is 20660881. The reversal of 20660880 is 8806602.

It is an interprime number because it is at equal distance from previous prime (20660879) and next prime (20660881).

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (20660881) 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, 6052 + ... + 8828.

Almost surely, 2^20660880 is an apocalyptic number.

20660880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20660880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33069312).

20660880 is an abundant number, since it is smaller than the sum of its proper divisors (45477744).

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

20660880 is a wasteful number, since it uses less digits than its factorization.

20660880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2824 (or 2818 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 20660880 is about 4545.4240726251. The cubic root of 20660880 is about 274.3992616435.

The spelling of 20660880 in words is "twenty million, six hundred sixty thousand, eight hundred eighty".