18527881 has 2 divisors, whose sum is σ = 18527882. Its totient is φ = 18527880.

The previous prime is 18527879. The next prime is 18527891. The reversal of 18527881 is 18872581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14288400 + 4239481 = 3780^2 + 2059^2 .

It is a cyclic number.

It is not a de Polignac number, because 18527881 - 2¹ = 18527879 is a prime.

It is a super-2 number, since 2×18527881² = 686564748700322, which contains 22 as substring.

Together with 18527879, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (18527891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9263940 + 9263941.

It is an arithmetic number, because the mean of its divisors is an integer number (9263941).

Almost surely, 2^18527881 is an apocalyptic number.

It is an amenable number.

18527881 is a deficient number, since it is larger than the sum of its proper divisors (1).

18527881 is an equidigital number, since it uses as much as digits as its factorization.

18527881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 35840, while the sum is 40.

The square root of 18527881 is about 4304.4025137062. The cubic root of 18527881 is about 264.6114205218.

The spelling of 18527881 in words is "eighteen million, five hundred twenty-seven thousand, eight hundred eighty-one".