164405987 has 4 divisors (see below), whose sum is σ = 164674800. Its totient is φ = 164137176.

The previous prime is 164405981. The next prime is 164405999. The reversal of 164405987 is 789504461.

164405987 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 164405987 - 2¹⁰ = 164404963 is a prime.

It is a super-3 number, since 3×164405987³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (164405981) 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, 133487 + ... + 134712.

It is an arithmetic number, because the mean of its divisors is an integer number (41168700).

Almost surely, 2^164405987 is an apocalyptic number.

164405987 is a deficient number, since it is larger than the sum of its proper divisors (268813).

164405987 is an equidigital number, since it uses as much as digits as its factorization.

164405987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268812.

The product of its (nonzero) digits is 241920, while the sum is 44.

The square root of 164405987 is about 12822.0898062679. The cubic root of 164405987 is about 547.8216726222.

The spelling of 164405987 in words is "one hundred sixty-four million, four hundred five thousand, nine hundred eighty-seven".