20604221 has 8 divisors (see below), whose sum is σ = 23799744. Its totient is φ = 17629120.

The previous prime is 20604211. The next prime is 20604247. The reversal of 20604221 is 12240602.

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

It is a cyclic number.

It is not a de Polignac number, because 20604221 - 2¹⁴ = 20587837 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20604221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20604211) 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, 54905 + ... + 55278.

It is an arithmetic number, because the mean of its divisors is an integer number (2974968).

Almost surely, 2^20604221 is an apocalyptic number.

It is an amenable number.

20604221 is a deficient number, since it is larger than the sum of its proper divisors (3195523).

20604221 is a wasteful number, since it uses less digits than its factorization.

20604221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110211.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 20604221 is about 4539.1872620547. The cubic root of 20604221 is about 274.1482006802.

Adding to 20604221 its reverse (12240602), we get a palindrome (32844823).

The spelling of 20604221 in words is "twenty million, six hundred four thousand, two hundred twenty-one".