20253515 has 4 divisors (see below), whose sum is σ = 24304224. Its totient is φ = 16202808.

The previous prime is 20253469. The next prime is 20253521. The reversal of 20253515 is 51535202.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20253515 - 2⁶ = 20253451 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2025347 + ... + 2025356.

It is an arithmetic number, because the mean of its divisors is an integer number (6076056).

Almost surely, 2^20253515 is an apocalyptic number.

20253515 is a deficient number, since it is larger than the sum of its proper divisors (4050709).

20253515 is an equidigital number, since it uses as much as digits as its factorization.

20253515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4050708.

The product of its (nonzero) digits is 1500, while the sum is 23.

The square root of 20253515 is about 4500.3905386088. The cubic root of 20253515 is about 272.5838588245.

Adding to 20253515 its reverse (51535202), we get a palindrome (71788717).

The spelling of 20253515 in words is "twenty million, two hundred fifty-three thousand, five hundred fifteen".