1340323021 has 4 divisors (see below), whose sum is σ = 1340584672. Its totient is φ = 1340061372.

The previous prime is 1340323013. The next prime is 1340323043. The reversal of 1340323021 is 1203230431.

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 1340323021 - 2³ = 1340323013 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 1340323021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1340323051) 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, 122985 + ... + 133438.

It is an arithmetic number, because the mean of its divisors is an integer number (335146168).

Almost surely, 2^1340323021 is an apocalyptic number.

It is an amenable number.

1340323021 is a deficient number, since it is larger than the sum of its proper divisors (261651).

1340323021 is an equidigital number, since it uses as much as digits as its factorization.

1340323021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261650.

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 1340323021 is about 36610.4223002139. The cubic root of 1340323021 is about 1102.5623519394.

Adding to 1340323021 its reverse (1203230431), we get a palindrome (2543553452).

The spelling of 1340323021 in words is "one billion, three hundred forty million, three hundred twenty-three thousand, twenty-one".