212111100021001 has 4 divisors (see below), whose sum is σ = 215016731528212. Its totient is φ = 209205468513792.

The previous prime is 212111100020987. The next prime is 212111100021013. The reversal of 212111100021001 is 100120001111212.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 103343387982025 + 108767712038976 = 10165795^2 + 10429176^2 .

It is a cyclic number.

It is not a de Polignac number, because 212111100021001 - 2¹³ = 212111100012809 is a prime.

It is a super-2 number, since 2×212111100021001² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (212111100021061) 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, 1452815753496 + ... + 1452815753641.

It is an arithmetic number, because the mean of its divisors is an integer number (53754182882053).

Almost surely, 2^{212111100021001} is an apocalyptic number.

It is an amenable number.

212111100021001 is a deficient number, since it is larger than the sum of its proper divisors (2905631507211).

212111100021001 is an equidigital number, since it uses as much as digits as its factorization.

212111100021001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2905631507210.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 212111100021001 its reverse (100120001111212), we get a palindrome (312231101132213).

The spelling of 212111100021001 in words is "two hundred twelve trillion, one hundred eleven billion, one hundred million, twenty-one thousand, one".