20645708 has 6 divisors (see below), whose sum is σ = 36129996. Its totient is φ = 10322852.

The previous prime is 20645707. The next prime is 20645711. The reversal of 20645708 is 80754602.

It is not an unprimeable number, because it can be changed into a prime (20645707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2580710 + ... + 2580717.

It is an arithmetic number, because the mean of its divisors is an integer number (6021666).

Almost surely, 2^20645708 is an apocalyptic number.

It is an amenable number.

20645708 is a deficient number, since it is larger than the sum of its proper divisors (15484288).

20645708 is a wasteful number, since it uses less digits than its factorization.

20645708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5161431 (or 5161429 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 32.

The square root of 20645708 is about 4543.7548349355. The cubic root of 20645708 is about 274.3320782343.

The spelling of 20645708 in words is "twenty million, six hundred forty-five thousand, seven hundred eight".