20440215 has 64 divisors (see below), whose sum is σ = 39398400. Its totient is φ = 10023552.

The previous prime is 20440213. The next prime is 20440249. The reversal of 20440215 is 51204402.

It is not a de Polignac number, because 20440215 - 2¹ = 20440213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20440213) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 89932 + ... + 90158.

It is an arithmetic number, because the mean of its divisors is an integer number (615600).

Almost surely, 2^20440215 is an apocalyptic number.

20440215 is a deficient number, since it is larger than the sum of its proper divisors (18958185).

20440215 is a wasteful number, since it uses less digits than its factorization.

20440215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 293 (or 287 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 20440215 is about 4521.0855997205. The cubic root of 20440215 is about 273.4188715364.

Adding to 20440215 its reverse (51204402), we get a palindrome (71644617).

The spelling of 20440215 in words is "twenty million, four hundred forty thousand, two hundred fifteen".