20216464 has 20 divisors (see below), whose sum is σ = 40433920. Its totient is φ = 9781920.

The previous prime is 20216447. The next prime is 20216477. The reversal of 20216464 is 46461202.

20216464 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19884 + ... + 20875.

It is an arithmetic number, because the mean of its divisors is an integer number (2021696).

Almost surely, 2^20216464 is an apocalyptic number.

It is an amenable number.

20216464 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20216464 is a wasteful number, since it uses less digits than its factorization.

20216464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40798 (or 40792 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 20216464 is about 4496.2722337510. The cubic root of 20216464 is about 272.4175392273.

Adding to 20216464 its reverse (46461202), we get a palindrome (66677666).

The spelling of 20216464 in words is "twenty million, two hundred sixteen thousand, four hundred sixty-four".