20212001201921 has 2 divisors, whose sum is σ = 20212001201922. Its totient is φ = 20212001201920.

The previous prime is 20212001201813. The next prime is 20212001201929. The reversal of 20212001201921 is 12910210021202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19261249447696 + 950751754225 = 4388764^2 + 975065^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20212001201921 is a prime.

It is a super-2 number, since 2×20212001201921² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20212001201929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10106000600960 + 10106000600961.

It is an arithmetic number, because the mean of its divisors is an integer number (10106000600961).

Almost surely, 2^{20212001201921} is an apocalyptic number.

It is an amenable number.

20212001201921 is a deficient number, since it is larger than the sum of its proper divisors (1).

20212001201921 is an equidigital number, since it uses as much as digits as its factorization.

20212001201921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 23.

The spelling of 20212001201921 in words is "twenty trillion, two hundred twelve billion, one million, two hundred one thousand, nine hundred twenty-one".