20312020221 has 16 divisors (see below), whose sum is σ = 27665854464. Its totient is φ = 13249911024.

The previous prime is 20312020213. The next prime is 20312020237. The reversal of 20312020221 is 12202021302.

It is a happy number.

It is not a de Polignac number, because 20312020221 - 2³ = 20312020213 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20312020221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20312020621) 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, 628176 + ... + 659718.

It is an arithmetic number, because the mean of its divisors is an integer number (1729115904).

Almost surely, 2^20312020221 is an apocalyptic number.

It is an amenable number.

20312020221 is a deficient number, since it is larger than the sum of its proper divisors (7353834243).

20312020221 is a wasteful number, since it uses less digits than its factorization.

20312020221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36160.

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 20312020221 its reverse (12202021302), we get a palindrome (32514041523).

The spelling of 20312020221 in words is "twenty billion, three hundred twelve million, twenty thousand, two hundred twenty-one".