21020211983 has 2 divisors, whose sum is σ = 21020211984. Its totient is φ = 21020211982.

The previous prime is 21020211967. The next prime is 21020212019. The reversal of 21020211983 is 38911202012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21020211983 - 2⁴ = 21020211967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21020216983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510105991 + 10510105992.

It is an arithmetic number, because the mean of its divisors is an integer number (10510105992).

Almost surely, 2^21020211983 is an apocalyptic number.

21020211983 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020211983 is an equidigital number, since it uses as much as digits as its factorization.

21020211983 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 21020211983 its reverse (38911202012), we get a palindrome (59931413995).

The spelling of 21020211983 in words is "twenty-one billion, twenty million, two hundred eleven thousand, nine hundred eighty-three".