81896687 has 2 divisors, whose sum is σ = 81896688. Its totient is φ = 81896686.

The previous prime is 81896677. The next prime is 81896741. The reversal of 81896687 is 78669818.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81896687 - 2⁴ = 81896671 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81896627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40948343 + 40948344.

It is an arithmetic number, because the mean of its divisors is an integer number (40948344).

Almost surely, 2^81896687 is an apocalyptic number.

81896687 is a deficient number, since it is larger than the sum of its proper divisors (1).

81896687 is an equidigital number, since it uses as much as digits as its factorization.

81896687 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1161216, while the sum is 53.

The square root of 81896687 is about 9049.6788340802. The cubic root of 81896687 is about 434.2656160369.

The spelling of 81896687 in words is "eighty-one million, eight hundred ninety-six thousand, six hundred eighty-seven".