20397015 has 20 divisors (see below), whose sum is σ = 36564264. Its totient is φ = 10878192.

The previous prime is 20396993. The next prime is 20397019. The reversal of 20397015 is 51079302.

It is not a de Polignac number, because 20397015 - 2⁵ = 20396983 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 20397015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20397019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 24777 + ... + 25586.

Almost surely, 2^20397015 is an apocalyptic number.

20397015 is a deficient number, since it is larger than the sum of its proper divisors (16167249).

20397015 is an equidigital number, since it uses as much as digits as its factorization.

20397015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50380 (or 50371 counting only the distinct ones).

The product of its (nonzero) digits is 1890, while the sum is 27.

The square root of 20397015 is about 4516.3054591115. The cubic root of 20397015 is about 273.2261138395.

The spelling of 20397015 in words is "twenty million, three hundred ninety-seven thousand, fifteen".