20216647 has 8 divisors (see below), whose sum is σ = 22384512. Its totient is φ = 18103800.

The previous prime is 20216641. The next prime is 20216659. The reversal of 20216647 is 74661202.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20216647 - 2³ = 20216639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20216641) 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, 12979 + ... + 14452.

It is an arithmetic number, because the mean of its divisors is an integer number (2798064).

Almost surely, 2^20216647 is an apocalyptic number.

20216647 is a deficient number, since it is larger than the sum of its proper divisors (2167865).

20216647 is a wasteful number, since it uses less digits than its factorization.

20216647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27509.

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 20216647 is about 4496.2925838962. The cubic root of 20216647 is about 272.4183612019.

Adding to 20216647 its reverse (74661202), we get a palindrome (94877849).

It can be divided in two parts, 2021 and 6647, that added together give a palindrome (8668).

The spelling of 20216647 in words is "twenty million, two hundred sixteen thousand, six hundred forty-seven".