2120001211621 has 2 divisors, whose sum is σ = 2120001211622. Its totient is φ = 2120001211620.

The previous prime is 2120001211619. The next prime is 2120001211631. The reversal of 2120001211621 is 1261121000212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1880151046596 + 239850165025 = 1371186^2 + 489745^2 .

It is a cyclic number.

It is not a de Polignac number, because 2120001211621 - 2¹ = 2120001211619 is a prime.

Together with 2120001211619, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2120001211631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060000605810 + 1060000605811.

It is an arithmetic number, because the mean of its divisors is an integer number (1060000605811).

Almost surely, 2^{2120001211621} is an apocalyptic number.

It is an amenable number.

2120001211621 is a deficient number, since it is larger than the sum of its proper divisors (1).

2120001211621 is an equidigital number, since it uses as much as digits as its factorization.

2120001211621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 2120001211621 its reverse (1261121000212), we get a palindrome (3381122211833).

The spelling of 2120001211621 in words is "two trillion, one hundred twenty billion, one million, two hundred eleven thousand, six hundred twenty-one".