166537687 has 4 divisors (see below), whose sum is σ = 173778480. Its totient is φ = 159296896.

The previous prime is 166537681. The next prime is 166537697. The reversal of 166537687 is 786735661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 786735661 = 443 ⋅1775927.

It is not a de Polignac number, because 166537687 - 2¹¹ = 166535639 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 166537687.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166537681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3620362 + ... + 3620407.

It is an arithmetic number, because the mean of its divisors is an integer number (43444620).

Almost surely, 2^166537687 is an apocalyptic number.

166537687 is a deficient number, since it is larger than the sum of its proper divisors (7240793).

166537687 is an equidigital number, since it uses as much as digits as its factorization.

166537687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7240792.

The product of its digits is 1270080, while the sum is 49.

The square root of 166537687 is about 12904.9481595239. The cubic root of 166537687 is about 550.1792110213.

The spelling of 166537687 in words is "one hundred sixty-six million, five hundred thirty-seven thousand, six hundred eighty-seven".