82691687 has 4 divisors (see below), whose sum is σ = 89052600. Its totient is φ = 76330776.

The previous prime is 82691681. The next prime is 82691717. The reversal of 82691687 is 78619628.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 82691687 - 2⁸ = 82691431 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82691681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3180437 + ... + 3180462.

It is an arithmetic number, because the mean of its divisors is an integer number (22263150).

Almost surely, 2^82691687 is an apocalyptic number.

82691687 is a deficient number, since it is larger than the sum of its proper divisors (6360913).

82691687 is a wasteful number, since it uses less digits than its factorization.

82691687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6360912.

The product of its digits is 290304, while the sum is 47.

The square root of 82691687 is about 9093.4969621153. The cubic root of 82691687 is about 435.6662832978. Note that the first 3 decimals are identical.

The spelling of 82691687 in words is "eighty-two million, six hundred ninety-one thousand, six hundred eighty-seven".