5638888181 has 2 divisors, whose sum is σ = 5638888182. Its totient is φ = 5638888180.

The previous prime is 5638888091. The next prime is 5638888187. The reversal of 5638888181 is 1818888365.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4416267025 + 1222621156 = 66455^2 + 34966^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5638888181 is a prime.

It is a super-2 number, since 2×5638888181² = 63594119835642977522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5638888187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2819444090 + 2819444091.

It is an arithmetic number, because the mean of its divisors is an integer number (2819444091).

Almost surely, 2^5638888181 is an apocalyptic number.

It is an amenable number.

5638888181 is a deficient number, since it is larger than the sum of its proper divisors (1).

5638888181 is an equidigital number, since it uses as much as digits as its factorization.

5638888181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2949120, while the sum is 56.

The square root of 5638888181 is about 75092.5307936815. The cubic root of 5638888181 is about 1779.9091167880.

The spelling of 5638888181 in words is "five billion, six hundred thirty-eight million, eight hundred eighty-eight thousand, one hundred eighty-one".