86887991 has 2 divisors, whose sum is σ = 86887992. Its totient is φ = 86887990.

The previous prime is 86887987. The next prime is 86888023. The reversal of 86887991 is 19978868.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 86887991 - 2² = 86887987 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (86887921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43443995 + 43443996.

It is an arithmetic number, because the mean of its divisors is an integer number (43443996).

Almost surely, 2^86887991 is an apocalyptic number.

86887991 is a deficient number, since it is larger than the sum of its proper divisors (1).

86887991 is an equidigital number, since it uses as much as digits as its factorization.

86887991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1741824, while the sum is 56.

The square root of 86887991 is about 9321.3728066203. The cubic root of 86887991 is about 442.9145206515.

It can be divided in two parts, 86887 and 991, that added together give a palindrome (87878).

The spelling of 86887991 in words is "eighty-six million, eight hundred eighty-seven thousand, nine hundred ninety-one".