20005215 has 16 divisors (see below), whose sum is σ = 33112800. Its totient is φ = 10301312.

The previous prime is 20005213. The next prime is 20005231. The reversal of 20005215 is 51250002.

It is a cyclic number.

It is not a de Polignac number, because 20005215 - 2¹ = 20005213 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a junction number, because it is equal to n+sod(n) for n = 20005194 and 20005203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20005213) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22560 + ... + 23429.

It is an arithmetic number, because the mean of its divisors is an integer number (2069550).

Almost surely, 2^20005215 is an apocalyptic number.

20005215 is a deficient number, since it is larger than the sum of its proper divisors (13107585).

20005215 is a wasteful number, since it uses less digits than its factorization.

20005215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46026.

The product of its (nonzero) digits is 100, while the sum is 15.

The square root of 20005215 is about 4472.7189717218. The cubic root of 20005215 is about 271.4653524223.

Adding to 20005215 its reverse (51250002), we get a palindrome (71255217).

The spelling of 20005215 in words is "twenty million, five thousand, two hundred fifteen".