87181111 has 2 divisors, whose sum is σ = 87181112. Its totient is φ = 87181110.

The previous prime is 87181103. The next prime is 87181153. The reversal of 87181111 is 11118178.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 87181111 - 2³ = 87181103 is a prime.

It is a super-2 number, since 2×87181111² = 15201092230388642, which contains 22 as substring.

It is equal to p_5063095 and since 87181111 and 5063095 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 87181111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87181411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43590555 + 43590556.

It is an arithmetic number, because the mean of its divisors is an integer number (43590556).

Almost surely, 2^87181111 is an apocalyptic number.

87181111 is a deficient number, since it is larger than the sum of its proper divisors (1).

87181111 is an equidigital number, since it uses as much as digits as its factorization.

87181111 is an evil number, because the sum of its binary digits is even.

The product of its digits is 448, while the sum is 28.

The square root of 87181111 is about 9337.0825743377. The cubic root of 87181111 is about 443.4120247122.

Adding to 87181111 its reverse (11118178), we get a palindrome (98299289).

The spelling of 87181111 in words is "eighty-seven million, one hundred eighty-one thousand, one hundred eleven".