1321124021 has 4 divisors (see below), whose sum is σ = 1509856032. Its totient is φ = 1132392012.

The previous prime is 1321123939. The next prime is 1321124027. The reversal of 1321124021 is 1204211231.

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 1321124021 - 2¹⁴ = 1321107637 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321124027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 94365995 + ... + 94366008.

It is an arithmetic number, because the mean of its divisors is an integer number (377464008).

Almost surely, 2^1321124021 is an apocalyptic number.

It is an amenable number.

1321124021 is a deficient number, since it is larger than the sum of its proper divisors (188732011).

1321124021 is an equidigital number, since it uses as much as digits as its factorization.

1321124021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188732010.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 1321124021 is about 36347.2697874270. The cubic root of 1321124021 is about 1097.2725876919.

Adding to 1321124021 its reverse (1204211231), we get a palindrome (2525335252).

The spelling of 1321124021 in words is "one billion, three hundred twenty-one million, one hundred twenty-four thousand, twenty-one".