20445321 has 24 divisors (see below), whose sum is σ = 30720256. Its totient is φ = 12022560.

The previous prime is 20445317. The next prime is 20445323. The reversal of 20445321 is 12354402.

It is not a de Polignac number, because 20445321 - 2² = 20445317 is a prime.

It is a super-2 number, since 2×20445321² = 836022301586082, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20445323) 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, 20136 + ... + 21126.

Almost surely, 2^20445321 is an apocalyptic number.

It is an amenable number.

20445321 is a deficient number, since it is larger than the sum of its proper divisors (10274935).

20445321 is a wasteful number, since it uses less digits than its factorization.

20445321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1053 (or 1030 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 20445321 is about 4521.6502518439. The cubic root of 20445321 is about 273.4416364718.

Adding to 20445321 its reverse (12354402), we get a palindrome (32799723).

The spelling of 20445321 in words is "twenty million, four hundred forty-five thousand, three hundred twenty-one".