20666420 has 24 divisors (see below), whose sum is σ = 45287424. Its totient is φ = 7906976.

The previous prime is 20666413. The next prime is 20666447. The reversal of 20666420 is 2466602.

It is a self number, because there is not a number n which added to its sum of digits gives 20666420.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22004 + ... + 22923.

It is an arithmetic number, because the mean of its divisors is an integer number (1886976).

Almost surely, 2^20666420 is an apocalyptic number.

20666420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20666420 is an abundant number, since it is smaller than the sum of its proper divisors (24621004).

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

20666420 is a wasteful number, since it uses less digits than its factorization.

20666420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44959 (or 44957 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 20666420 is about 4546.0334358647. The cubic root of 20666420 is about 274.4237852207.

The spelling of 20666420 in words is "twenty million, six hundred sixty-six thousand, four hundred twenty".