2100121399 has 2 divisors, whose sum is σ = 2100121400. Its totient is φ = 2100121398.

The previous prime is 2100121379. The next prime is 2100121409. The reversal of 2100121399 is 9931210012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2100121399 - 2⁷ = 2100121271 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2100121379) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050060699 + 1050060700.

It is an arithmetic number, because the mean of its divisors is an integer number (1050060700).

Almost surely, 2^2100121399 is an apocalyptic number.

2100121399 is a deficient number, since it is larger than the sum of its proper divisors (1).

2100121399 is an equidigital number, since it uses as much as digits as its factorization.

2100121399 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 2100121399 is about 45827.0815020987. The cubic root of 2100121399 is about 1280.6038408660.

The spelling of 2100121399 in words is "two billion, one hundred million, one hundred twenty-one thousand, three hundred ninety-nine".