20715265 has 8 divisors (see below), whose sum is σ = 26320680. Its totient is φ = 15597312.

The previous prime is 20715241. The next prime is 20715271. The reversal of 20715265 is 56251702.

It can be written as a sum of positive squares in 4 ways, for example, as 3732624 + 16982641 = 1932^2 + 4121^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20715265 is a prime.

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, 121770 + ... + 121939.

It is an arithmetic number, because the mean of its divisors is an integer number (3290085).

Almost surely, 2^20715265 is an apocalyptic number.

It is an amenable number.

20715265 is a deficient number, since it is larger than the sum of its proper divisors (5605415).

20715265 is a wasteful number, since it uses less digits than its factorization.

20715265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243731.

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 20715265 is about 4551.4025310886. The cubic root of 20715265 is about 274.6398149500.

Adding to 20715265 its reverse (56251702), we get a palindrome (76966967).

The spelling of 20715265 in words is "twenty million, seven hundred fifteen thousand, two hundred sixty-five".