21312131103001 has 4 divisors (see below), whose sum is σ = 21313766359732. Its totient is φ = 21310495846272.

The previous prime is 21312131102981. The next prime is 21312131103013. The reversal of 21312131103001 is 10030113121312.

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 9874552064400 + 11437579038601 = 3142380^2 + 3381949^2 .

It is a cyclic number.

It is not a de Polignac number, because 21312131103001 - 2³⁹ = 20762375289113 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21312131103001.

It is not an unprimeable number, because it can be changed into a prime (21312131103031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 817608816 + ... + 817634881.

It is an arithmetic number, because the mean of its divisors is an integer number (5328441589933).

Almost surely, 2^{21312131103001} is an apocalyptic number.

It is an amenable number.

21312131103001 is a deficient number, since it is larger than the sum of its proper divisors (1635256731).

21312131103001 is a wasteful number, since it uses less digits than its factorization.

21312131103001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1635256730.

The product of its (nonzero) digits is 108, while the sum is 19.

Adding to 21312131103001 its reverse (10030113121312), we get a palindrome (31342244224313).

The spelling of 21312131103001 in words is "twenty-one trillion, three hundred twelve billion, one hundred thirty-one million, one hundred three thousand, one".