20115513 has 32 divisors (see below), whose sum is σ = 32918400. Its totient is φ = 12038400.

The previous prime is 20115503. The next prime is 20115521. The reversal of 20115513 is 31551102.

It is not a de Polignac number, because 20115513 - 2⁵ = 20115481 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20115503) 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, 26053 + ... + 26813.

It is an arithmetic number, because the mean of its divisors is an integer number (1028700).

Almost surely, 2^20115513 is an apocalyptic number.

It is an amenable number.

20115513 is a deficient number, since it is larger than the sum of its proper divisors (12802887).

20115513 is a wasteful number, since it uses less digits than its factorization.

20115513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 870 (or 864 counting only the distinct ones).

The product of its (nonzero) digits is 150, while the sum is 18.

The square root of 20115513 is about 4485.0321069085. The cubic root of 20115513 is about 271.9633429911.

Adding to 20115513 its reverse (31551102), we get a palindrome (51666615).

It can be divided in two parts, 201 and 15513, that multiplied together give a palindrome (3118113).

The spelling of 20115513 in words is "twenty million, one hundred fifteen thousand, five hundred thirteen".