1820445149 has 2 divisors, whose sum is σ = 1820445150. Its totient is φ = 1820445148.

The previous prime is 1820445131. The next prime is 1820445163. The reversal of 1820445149 is 9415440281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1748076100 + 72369049 = 41810^2 + 8507^2 .

It is a cyclic number.

It is not a de Polignac number, because 1820445149 - 2²⁴ = 1803667933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1820441149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 910222574 + 910222575.

It is an arithmetic number, because the mean of its divisors is an integer number (910222575).

Almost surely, 2^1820445149 is an apocalyptic number.

It is an amenable number.

1820445149 is a deficient number, since it is larger than the sum of its proper divisors (1).

1820445149 is an equidigital number, since it uses as much as digits as its factorization.

1820445149 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46080, while the sum is 38.

The square root of 1820445149 is about 42666.6749231763. The cubic root of 1820445149 is about 1221.0286829126.

The spelling of 1820445149 in words is "one billion, eight hundred twenty million, four hundred forty-five thousand, one hundred forty-nine".