166647887 has 4 divisors (see below), whose sum is σ = 190454736. Its totient is φ = 142841040.

The previous prime is 166647839. The next prime is 166647907. The reversal of 166647887 is 788746661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 788746661 = 487 ⋅1619603.

It is a cyclic number.

It is not a de Polignac number, because 166647887 - 2⁶ = 166647823 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166647487) 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, 11903414 + ... + 11903427.

It is an arithmetic number, because the mean of its divisors is an integer number (47613684).

Almost surely, 2^166647887 is an apocalyptic number.

166647887 is a deficient number, since it is larger than the sum of its proper divisors (23806849).

166647887 is an equidigital number, since it uses as much as digits as its factorization.

166647887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23806848.

The product of its digits is 2709504, while the sum is 53.

The square root of 166647887 is about 12909.2171335058. The cubic root of 166647887 is about 550.3005376750.

The spelling of 166647887 in words is "one hundred sixty-six million, six hundred forty-seven thousand, eight hundred eighty-seven".