199553581 has 2 divisors, whose sum is σ = 199553582. Its totient is φ = 199553580.

The previous prime is 199553569. The next prime is 199553591. The reversal of 199553581 is 185355991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 199233225 + 320356 = 14115^2 + 566^2 .

It is an emirp because it is prime and its reverse (185355991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199553581 - 2¹¹ = 199551533 is a prime.

It is a super-2 number, since 2×199553581² = 79643263379847122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199553521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99776790 + 99776791.

It is an arithmetic number, because the mean of its divisors is an integer number (99776791).

Almost surely, 2^199553581 is an apocalyptic number.

It is an amenable number.

199553581 is a deficient number, since it is larger than the sum of its proper divisors (1).

199553581 is an equidigital number, since it uses as much as digits as its factorization.

199553581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 243000, while the sum is 46.

The square root of 199553581 is about 14126.3435113266. The cubic root of 199553581 is about 584.3681111449.

The spelling of 199553581 in words is "one hundred ninety-nine million, five hundred fifty-three thousand, five hundred eighty-one".