1821427 has 2 divisors, whose sum is σ = 1821428. Its totient is φ = 1821426.

The previous prime is 1821409. The next prime is 1821433. The reversal of 1821427 is 7241281.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (7241281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1821427 - 2¹⁵ = 1788659 is a prime.

It is an Ulam number.

It is a plaindrome in base 14.

It is not a weakly prime, because it can be changed into another prime (1821487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910713 + 910714.

It is an arithmetic number, because the mean of its divisors is an integer number (910714).

2^1821427 is an apocalyptic number.

1821427 is a deficient number, since it is larger than the sum of its proper divisors (1).

1821427 is an equidigital number, since it uses as much as digits as its factorization.

1821427 is an evil number, because the sum of its binary digits is even.

The product of its digits is 896, while the sum is 25.

The square root of 1821427 is about 1349.6025340818. The cubic root of 1821427 is about 122.1248162704.

The spelling of 1821427 in words is "one million, eight hundred twenty-one thousand, four hundred twenty-seven".