1304343021 has 4 divisors (see below), whose sum is σ = 1739124032. Its totient is φ = 869562012.

The previous prime is 1304342999. The next prime is 1304343043. The reversal of 1304343021 is 1203434031.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1203434031 = 3 ⋅401144677.

It is an interprime number because it is at equal distance from previous prime (1304342999) and next prime (1304343043).

It is not a de Polignac number, because 1304343021 - 2¹⁴ = 1304326637 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 (1304343221) 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, 217390501 + ... + 217390506.

It is an arithmetic number, because the mean of its divisors is an integer number (434781008).

Almost surely, 2^1304343021 is an apocalyptic number.

It is an amenable number.

1304343021 is a deficient number, since it is larger than the sum of its proper divisors (434781011).

1304343021 is an equidigital number, since it uses as much as digits as its factorization.

1304343021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434781010.

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 1304343021 is about 36115.6894022529. The cubic root of 1304343021 is about 1092.6069019351.

Adding to 1304343021 its reverse (1203434031), we get a palindrome (2507777052).

The spelling of 1304343021 in words is "one billion, three hundred four million, three hundred forty-three thousand, twenty-one".