1304020391 has 2 divisors, whose sum is σ = 1304020392. Its totient is φ = 1304020390.

The previous prime is 1304020349. The next prime is 1304020423. The reversal of 1304020391 is 1930204031.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1304020391 - 2⁶ = 1304020327 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1304020691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 652010195 + 652010196.

It is an arithmetic number, because the mean of its divisors is an integer number (652010196).

Almost surely, 2^1304020391 is an apocalyptic number.

1304020391 is a deficient number, since it is larger than the sum of its proper divisors (1).

1304020391 is an equidigital number, since it uses as much as digits as its factorization.

1304020391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 1304020391 is about 36111.2225076914. Note that the first 3 decimals coincide. The cubic root of 1304020391 is about 1092.5168088570.

The spelling of 1304020391 in words is "one billion, three hundred four million, twenty thousand, three hundred ninety-one".