1321220350421 has 4 divisors (see below), whose sum is σ = 1346149036332. Its totient is φ = 1296291664512.

The previous prime is 1321220350391. The next prime is 1321220350451. The reversal of 1321220350421 is 1240530221231.

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

It is an interprime number because it is at equal distance from previous prime (1321220350391) and next prime (1321220350451).

It can be written as a sum of positive squares in 2 ways, for example, as 529458514321 + 791761836100 = 727639^2 + 889810^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1321220350421 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 (1321220350451) 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, 12464342876 + ... + 12464342981.

It is an arithmetic number, because the mean of its divisors is an integer number (336537259083).

Almost surely, 2^{1321220350421} is an apocalyptic number.

It is an amenable number.

1321220350421 is a deficient number, since it is larger than the sum of its proper divisors (24928685911).

1321220350421 is an equidigital number, since it uses as much as digits as its factorization.

1321220350421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24928685910.

The product of its (nonzero) digits is 2880, while the sum is 26.

Adding to 1321220350421 its reverse (1240530221231), we get a palindrome (2561750571652).

The spelling of 1321220350421 in words is "one trillion, three hundred twenty-one billion, two hundred twenty million, three hundred fifty thousand, four hundred twenty-one".