1836642221 has 2 divisors, whose sum is σ = 1836642222. Its totient is φ = 1836642220.

The previous prime is 1836642179. The next prime is 1836642263. The reversal of 1836642221 is 1222466381.

It is a balanced prime because it is at equal distance from previous prime (1836642179) and next prime (1836642263).

It can be written as a sum of positive squares in only one way, i.e., 1758124900 + 78517321 = 41930^2 + 8861^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1836642221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1836642121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 918321110 + 918321111.

It is an arithmetic number, because the mean of its divisors is an integer number (918321111).

Almost surely, 2^1836642221 is an apocalyptic number.

It is an amenable number.

1836642221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1836642221 is an equidigital number, since it uses as much as digits as its factorization.

1836642221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27648, while the sum is 35.

The square root of 1836642221 is about 42856.0639933254. The cubic root of 1836642221 is about 1224.6392876035.

The spelling of 1836642221 in words is "one billion, eight hundred thirty-six million, six hundred forty-two thousand, two hundred twenty-one".