381554809 has 2 divisors, whose sum is σ = 381554810. Its totient is φ = 381554808.

The previous prime is 381554773. The next prime is 381554813. The reversal of 381554809 is 908455183.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 255104784 + 126450025 = 15972^2 + 11245^2 .

It is a cyclic number.

It is not a de Polignac number, because 381554809 - 2¹¹ = 381552761 is a prime.

It is not a weakly prime, because it can be changed into another prime (381554209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190777404 + 190777405.

It is an arithmetic number, because the mean of its divisors is an integer number (190777405).

Almost surely, 2^381554809 is an apocalyptic number.

It is an amenable number.

381554809 is a deficient number, since it is larger than the sum of its proper divisors (1).

381554809 is an equidigital number, since it uses as much as digits as its factorization.

381554809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 172800, while the sum is 43.

The square root of 381554809 is about 19533.4279889629. The cubic root of 381554809 is about 725.3021706726.

The spelling of 381554809 in words is "three hundred eighty-one million, five hundred fifty-four thousand, eight hundred nine".