2121000120509 has 2 divisors, whose sum is σ = 2121000120510. Its totient is φ = 2121000120508.

The previous prime is 2121000120479. The next prime is 2121000120527. The reversal of 2121000120509 is 9050210001212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1333743194884 + 787256925625 = 1154878^2 + 887275^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121000120509 - 2¹⁶ = 2121000054973 is a prime.

It is a super-2 number, since 2×2121000120509² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121000120559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060500060254 + 1060500060255.

It is an arithmetic number, because the mean of its divisors is an integer number (1060500060255).

Almost surely, 2^{2121000120509} is an apocalyptic number.

It is an amenable number.

2121000120509 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121000120509 is an equidigital number, since it uses as much as digits as its factorization.

2121000120509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 360, while the sum is 23.

The spelling of 2121000120509 in words is "two trillion, one hundred twenty-one billion, one hundred twenty thousand, five hundred nine".