164405986 has 4 divisors (see below), whose sum is σ = 246608982. Its totient is φ = 82202992.

The previous prime is 164405981. The next prime is 164405999. The reversal of 164405986 is 689504461.

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

It can be written as a sum of positive squares in only one way, i.e., 157979761 + 6426225 = 12569^2 + 2535^2 .

It is a super-3 number, since 3×164405986³ (a number of 26 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (164405981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41101495 + ... + 41101498.

Almost surely, 2^164405986 is an apocalyptic number.

164405986 is a deficient number, since it is larger than the sum of its proper divisors (82202996).

164405986 is an equidigital number, since it uses as much as digits as its factorization.

164405986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82202995.

The product of its (nonzero) digits is 207360, while the sum is 43.

The square root of 164405986 is about 12822.0897672727. The cubic root of 164405986 is about 547.8216715115.

The spelling of 164405986 in words is "one hundred sixty-four million, four hundred five thousand, nine hundred eighty-six".