20011221983 has 2 divisors, whose sum is σ = 20011221984. Its totient is φ = 20011221982.

The previous prime is 20011221961. The next prime is 20011222003. The reversal of 20011221983 is 38912211002.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20011221983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20011221943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10005610991 + 10005610992.

It is an arithmetic number, because the mean of its divisors is an integer number (10005610992).

Almost surely, 2^20011221983 is an apocalyptic number.

20011221983 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011221983 is an equidigital number, since it uses as much as digits as its factorization.

20011221983 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 29.

Adding to 20011221983 its reverse (38912211002), we get a palindrome (58923432985).

The spelling of 20011221983 in words is "twenty billion, eleven million, two hundred twenty-one thousand, nine hundred eighty-three".