20021201001979 has 2 divisors, whose sum is σ = 20021201001980. Its totient is φ = 20021201001978.

The previous prime is 20021201001943. The next prime is 20021201002027. The reversal of 20021201001979 is 97910010212002.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20021201001979 - 2¹⁷ = 20021200870907 is a prime.

It is not a weakly prime, because it can be changed into another prime (20021201001929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10010600500989 + 10010600500990.

It is an arithmetic number, because the mean of its divisors is an integer number (10010600500990).

Almost surely, 2^{20021201001979} is an apocalyptic number.

20021201001979 is a deficient number, since it is larger than the sum of its proper divisors (1).

20021201001979 is an equidigital number, since it uses as much as digits as its factorization.

20021201001979 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4536, while the sum is 34.

The spelling of 20021201001979 in words is "twenty trillion, twenty-one billion, two hundred one million, one thousand, nine hundred seventy-nine".