3638433581 has 2 divisors, whose sum is σ = 3638433582. Its totient is φ = 3638433580.

The previous prime is 3638433569. The next prime is 3638433587. The reversal of 3638433581 is 1853348363.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1888684681 + 1749748900 = 43459^2 + 41830^2 .

It is an emirp because it is prime and its reverse (1853348363) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3638433581 is a prime.

It is a super-2 number, since 2×3638433581² = 26476397846696967122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3638433587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1819216790 + 1819216791.

It is an arithmetic number, because the mean of its divisors is an integer number (1819216791).

Almost surely, 2^3638433581 is an apocalyptic number.

It is an amenable number.

3638433581 is a deficient number, since it is larger than the sum of its proper divisors (1).

3638433581 is an equidigital number, since it uses as much as digits as its factorization.

3638433581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 622080, while the sum is 44.

The square root of 3638433581 is about 60319.4295480320. The cubic root of 3638433581 is about 1538.0536468306.

The spelling of 3638433581 in words is "three billion, six hundred thirty-eight million, four hundred thirty-three thousand, five hundred eighty-one".