1791421 has 2 divisors, whose sum is σ = 1791422. Its totient is φ = 1791420.

The previous prime is 1791407. The next prime is 1791431. The reversal of 1791421 is 1241971.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1466521 + 324900 = 1211^2 + 570^2 .

It is an emirp because it is prime and its reverse (1241971) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1791421 - 2¹¹ = 1789373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1791431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 895710 + 895711.

It is an arithmetic number, because the mean of its divisors is an integer number (895711).

2^1791421 is an apocalyptic number.

It is an amenable number.

1791421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1791421 is an equidigital number, since it uses as much as digits as its factorization.

1791421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 504, while the sum is 25.

The square root of 1791421 is about 1338.4397633065. The cubic root of 1791421 is about 121.4504757321.

It can be divided in two parts, 179 and 1421, that added together give a square (1600 = 40²).

The spelling of 1791421 in words is "one million, seven hundred ninety-one thousand, four hundred twenty-one".