20423120221 has 16 divisors (see below), whose sum is σ = 24843110400. Its totient is φ = 16389515520.

The previous prime is 20423120213. The next prime is 20423120239. The reversal of 20423120221 is 12202132402.

It is not a de Polignac number, because 20423120221 - 2³ = 20423120213 is a prime.

It is a super-2 number, since 2×20423120221² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20423120321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 426546 + ... + 472003.

It is an arithmetic number, because the mean of its divisors is an integer number (1552694400).

Almost surely, 2^20423120221 is an apocalyptic number.

It is an amenable number.

20423120221 is a deficient number, since it is larger than the sum of its proper divisors (4419990179).

20423120221 is a wasteful number, since it uses less digits than its factorization.

20423120221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 898764.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 20423120221 its reverse (12202132402), we get a palindrome (32625252623).

The spelling of 20423120221 in words is "twenty billion, four hundred twenty-three million, one hundred twenty thousand, two hundred twenty-one".