87814891 has 2 divisors, whose sum is σ = 87814892. Its totient is φ = 87814890.

The previous prime is 87814889. The next prime is 87814921. The reversal of 87814891 is 19841878.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 87814891 - 2¹ = 87814889 is a prime.

It is a super-2 number, since 2×87814891² = 15422910162683762, which contains 22 as substring.

Together with 87814889, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (87814091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43907445 + 43907446.

It is an arithmetic number, because the mean of its divisors is an integer number (43907446).

Almost surely, 2^87814891 is an apocalyptic number.

87814891 is a deficient number, since it is larger than the sum of its proper divisors (1).

87814891 is an equidigital number, since it uses as much as digits as its factorization.

87814891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129024, while the sum is 46.

The square root of 87814891 is about 9370.9599828406. The cubic root of 87814891 is about 444.4839213522.

The spelling of 87814891 in words is "eighty-seven million, eight hundred fourteen thousand, eight hundred ninety-one".