20865249 has 32 divisors (see below), whose sum is σ = 32976000. Its totient is φ = 13001472.

The previous prime is 20865217. The next prime is 20865253. The reversal of 20865249 is 94256802.

20865249 = 467² + 468² + ... + 547².

It is a happy number.

It is not a de Polignac number, because 20865249 - 2⁵ = 20865217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20865259) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 45429 + ... + 45885.

It is an arithmetic number, because the mean of its divisors is an integer number (1030500).

Almost surely, 2^20865249 is an apocalyptic number.

It is an amenable number.

20865249 is a deficient number, since it is larger than the sum of its proper divisors (12110751).

20865249 is a wasteful number, since it uses less digits than its factorization.

20865249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 574 (or 568 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 20865249 is about 4567.8494940179. The cubic root of 20865249 is about 275.3010433295.

The spelling of 20865249 in words is "twenty million, eight hundred sixty-five thousand, two hundred forty-nine".