1821223057 has 2 divisors, whose sum is σ = 1821223058. Its totient is φ = 1821223056.

The previous prime is 1821223049. The next prime is 1821223081. The reversal of 1821223057 is 7503221281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 973190416 + 848032641 = 31196^2 + 29121^2 .

It is a cyclic number.

It is not a de Polignac number, because 1821223057 - 2³ = 1821223049 is a prime.

It is not a weakly prime, because it can be changed into another prime (1821223087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910611528 + 910611529.

It is an arithmetic number, because the mean of its divisors is an integer number (910611529).

Almost surely, 2^1821223057 is an apocalyptic number.

It is an amenable number.

1821223057 is a deficient number, since it is larger than the sum of its proper divisors (1).

1821223057 is an equidigital number, since it uses as much as digits as its factorization.

1821223057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 1821223057 is about 42675.7900571272. The cubic root of 1821223057 is about 1221.2025804376.

The spelling of 1821223057 in words is "one billion, eight hundred twenty-one million, two hundred twenty-three thousand, fifty-seven".