20321221312 has 28 divisors (see below), whose sum is σ = 46085627920. Its totient is φ = 8709094656.

The previous prime is 20321221309. The next prime is 20321221331. The reversal of 20321221312 is 21312212302.

It is a tau number, because it is divible by the number of its divisors (28).

It is a super-2 number, since 2×20321221312² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20321221312.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22679487 + ... + 22680382.

Almost surely, 2^20321221312 is an apocalyptic number.

It is an amenable number.

20321221312 is an abundant number, since it is smaller than the sum of its proper divisors (25764406608).

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

20321221312 is an equidigital number, since it uses as much as digits as its factorization.

20321221312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45359888 (or 45359878 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 20321221312 its reverse (21312212302), we get a palindrome (41633433614).

The spelling of 20321221312 in words is "twenty billion, three hundred twenty-one million, two hundred twenty-one thousand, three hundred twelve".