81888201 has 24 divisors (see below), whose sum is σ = 125975304. Its totient is φ = 51079680.

The previous prime is 81888197. The next prime is 81888221. The reversal of 81888201 is 10288818.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 76176 + 81812025 = 276^2 + 9045^2 .

It is not a de Polignac number, because 81888201 - 2² = 81888197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81888221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26215 + ... + 29171.

It is an arithmetic number, because the mean of its divisors is an integer number (5248971).

Almost surely, 2^81888201 is an apocalyptic number.

It is an amenable number.

81888201 is a deficient number, since it is larger than the sum of its proper divisors (44087103).

81888201 is a wasteful number, since it uses less digits than its factorization.

81888201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3161 (or 3158 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 36.

The square root of 81888201 is about 9049.2099655163. The cubic root of 81888201 is about 434.2506162225.

The spelling of 81888201 in words is "eighty-one million, eight hundred eighty-eight thousand, two hundred one".