21102120101001 has 4 divisors (see below), whose sum is σ = 28136160134672. Its totient is φ = 14068080067332.

The previous prime is 21102120100993. The next prime is 21102120101003. The reversal of 21102120101001 is 10010102120112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21102120101001 - 2³ = 21102120100993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21102120101003) 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, 3517020016831 + ... + 3517020016836.

It is an arithmetic number, because the mean of its divisors is an integer number (7034040033668).

Almost surely, 2^{21102120101001} is an apocalyptic number.

It is an amenable number.

21102120101001 is a deficient number, since it is larger than the sum of its proper divisors (7034040033671).

21102120101001 is an equidigital number, since it uses as much as digits as its factorization.

21102120101001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7034040033670.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21102120101001 its reverse (10010102120112), we get a palindrome (31112222221113).

The spelling of 21102120101001 in words is "twenty-one trillion, one hundred two billion, one hundred twenty million, one hundred one thousand, one".