20215516 has 24 divisors (see below), whose sum is σ = 37630656. Its totient is φ = 9469440.

The previous prime is 20215513. The next prime is 20215529. The reversal of 20215516 is 61551202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20215513) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17880 + ... + 18976.

It is an arithmetic number, because the mean of its divisors is an integer number (1567944).

Almost surely, 2^20215516 is an apocalyptic number.

It is an amenable number.

20215516 is a deficient number, since it is larger than the sum of its proper divisors (17415140).

20215516 is a wasteful number, since it uses less digits than its factorization.

20215516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1389 (or 1387 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 20215516 is about 4496.1668118521. The cubic root of 20215516 is about 272.4132810500.

Adding to 20215516 its reverse (61551202), we get a palindrome (81766718).

The spelling of 20215516 in words is "twenty million, two hundred fifteen thousand, five hundred sixteen".