20688244 has 6 divisors (see below), whose sum is σ = 36204434. Its totient is φ = 10344120.

The previous prime is 20688209. The next prime is 20688251. The reversal of 20688244 is 44288602.

It can be written as a sum of positive squares in only one way, i.e., 20250000 + 438244 = 4500^2 + 662^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2586027 + ... + 2586034.

Almost surely, 2^20688244 is an apocalyptic number.

It is an amenable number.

20688244 is a deficient number, since it is larger than the sum of its proper divisors (15516190).

20688244 is a wasteful number, since it uses less digits than its factorization.

20688244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5172065 (or 5172063 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 34.

The square root of 20688244 is about 4548.4331368066. The cubic root of 20688244 is about 274.5203495630.

The spelling of 20688244 in words is "twenty million, six hundred eighty-eight thousand, two hundred forty-four".