210001210121999 has 4 divisors (see below), whose sum is σ = 211067206112664. Its totient is φ = 208935214131336.

The previous prime is 210001210121993. The next prime is 210001210122017. The reversal of 210001210121999 is 999121012100012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-210001210121999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210001210121993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 532997995037 + ... + 532997995430.

It is an arithmetic number, because the mean of its divisors is an integer number (52766801528166).

Almost surely, 2^{210001210121999} is an apocalyptic number.

210001210121999 is a deficient number, since it is larger than the sum of its proper divisors (1065995990665).

210001210121999 is a wasteful number, since it uses less digits than its factorization.

210001210121999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1065995990664.

The product of its (nonzero) digits is 5832, while the sum is 38.

The spelling of 210001210121999 in words is "two hundred ten trillion, one billion, two hundred ten million, one hundred twenty-one thousand, nine hundred ninety-nine".