1821261223 has 2 divisors, whose sum is σ = 1821261224. Its totient is φ = 1821261222.

The previous prime is 1821261193. The next prime is 1821261227. The reversal of 1821261223 is 3221621281.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1821261223 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1821261191 and 1821261200.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1821261227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910630611 + 910630612.

It is an arithmetic number, because the mean of its divisors is an integer number (910630612).

Almost surely, 2^1821261223 is an apocalyptic number.

1821261223 is a deficient number, since it is larger than the sum of its proper divisors (1).

1821261223 is an equidigital number, since it uses as much as digits as its factorization.

1821261223 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2304, while the sum is 28.

The square root of 1821261223 is about 42676.2372169806. The cubic root of 1821261223 is about 1221.2111109856.

The spelling of 1821261223 in words is "one billion, eight hundred twenty-one million, two hundred sixty-one thousand, two hundred twenty-three".