164430781 has 4 divisors (see below), whose sum is σ = 164456512. Its totient is φ = 164405052.

The previous prime is 164430767. The next prime is 164430907. The reversal of 164430781 is 187034461.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 164430781 - 2¹⁹ = 163906493 is a prime.

It is a super-3 number, since 3×164430781³ (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 a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164430281) 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, 4876 + ... + 18778.

It is an arithmetic number, because the mean of its divisors is an integer number (41114128).

Almost surely, 2^164430781 is an apocalyptic number.

It is an amenable number.

164430781 is a deficient number, since it is larger than the sum of its proper divisors (25731).

164430781 is a wasteful number, since it uses less digits than its factorization.

164430781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25730.

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 164430781 is about 12823.0566168913. The cubic root of 164430781 is about 547.8492101591.

The spelling of 164430781 in words is "one hundred sixty-four million, four hundred thirty thousand, seven hundred eighty-one".