20438715 has 24 divisors (see below), whose sum is σ = 35948304. Its totient is φ = 9908800.

The previous prime is 20438711. The next prime is 20438729. The reversal of 20438715 is 51783402.

It is not a de Polignac number, because 20438715 - 2² = 20438711 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20438711) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3816 + ... + 7445.

It is an arithmetic number, because the mean of its divisors is an integer number (1497846).

Almost surely, 2^20438715 is an apocalyptic number.

20438715 is a deficient number, since it is larger than the sum of its proper divisors (15509589).

20438715 is a wasteful number, since it uses less digits than its factorization.

20438715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11291 (or 11280 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 20438715 is about 4520.9197073162. The cubic root of 20438715 is about 273.4121831145.

It can be divided in two parts, 204387 and 15, that added together give a palindrome (204402).

The spelling of 20438715 in words is "twenty million, four hundred thirty-eight thousand, seven hundred fifteen".