1321131010021 has 4 divisors (see below), whose sum is σ = 1323307503232. Its totient is φ = 1318954516812.

The previous prime is 1321131009997. The next prime is 1321131010039. The reversal of 1321131010021 is 1200101311231.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 1321131010021 - 2²⁷ = 1320996792293 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1321131009977 and 1321131010004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321131010421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1088245695 + ... + 1088246908.

It is an arithmetic number, because the mean of its divisors is an integer number (330826875808).

Almost surely, 2^{1321131010021} is an apocalyptic number.

It is an amenable number.

1321131010021 is a deficient number, since it is larger than the sum of its proper divisors (2176493211).

1321131010021 is an equidigital number, since it uses as much as digits as its factorization.

1321131010021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2176493210.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 1321131010021 its reverse (1200101311231), we get a palindrome (2521232321252).

The spelling of 1321131010021 in words is "one trillion, three hundred twenty-one billion, one hundred thirty-one million, ten thousand, twenty-one".