20121221983 has 2 divisors, whose sum is σ = 20121221984. Its totient is φ = 20121221982.

The previous prime is 20121221971. The next prime is 20121222001. The reversal of 20121221983 is 38912212102.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20121221983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20121221903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060610991 + 10060610992.

It is an arithmetic number, because the mean of its divisors is an integer number (10060610992).

Almost surely, 2^20121221983 is an apocalyptic number.

20121221983 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121221983 is an equidigital number, since it uses as much as digits as its factorization.

20121221983 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 31.

The spelling of 20121221983 in words is "twenty billion, one hundred twenty-one million, two hundred twenty-one thousand, nine hundred eighty-three".