165642387 has 4 divisors (see below), whose sum is σ = 220856520. Its totient is φ = 110428256.

The previous prime is 165642359. The next prime is 165642413. The reversal of 165642387 is 783246561.

165642387 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 165642387 - 2¹¹ = 165640339 is a prime.

It is not an unprimeable number, because it can be changed into a prime (165642317) 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, 27607062 + ... + 27607067.

It is an arithmetic number, because the mean of its divisors is an integer number (55214130).

Almost surely, 2^165642387 is an apocalyptic number.

165642387 is a deficient number, since it is larger than the sum of its proper divisors (55214133).

165642387 is an equidigital number, since it uses as much as digits as its factorization.

165642387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55214132.

The product of its digits is 241920, while the sum is 42.

The square root of 165642387 is about 12870.2131683978. The cubic root of 165642387 is about 549.1915251088.

The spelling of 165642387 in words is "one hundred sixty-five million, six hundred forty-two thousand, three hundred eighty-seven".