20868849 has 6 divisors (see below), whose sum is σ = 30143906. Its totient is φ = 13912560.

The previous prime is 20868847. The next prime is 20868853. The reversal of 20868849 is 94886802.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 11778624 + 9090225 = 3432^2 + 3015^2 .

It is not a de Polignac number, because 20868849 - 2¹ = 20868847 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20868847) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1159372 + ... + 1159389.

Almost surely, 2^20868849 is an apocalyptic number.

It is an amenable number.

20868849 is a deficient number, since it is larger than the sum of its proper divisors (9275057).

20868849 is a wasteful number, since it uses less digits than its factorization.

20868849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2318767 (or 2318764 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 45.

The square root of 20868849 is about 4568.2435355397. The cubic root of 20868849 is about 275.3168755035.

The spelling of 20868849 in words is "twenty million, eight hundred sixty-eight thousand, eight hundred forty-nine".