164402581 has 8 divisors (see below), whose sum is σ = 192967040. Its totient is φ = 137107728.

The previous prime is 164402561. The next prime is 164402599. The reversal of 164402581 is 185204461.

164402581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 164402581 - 2⁷ = 164402453 is a prime.

It is a super-3 number, since 3×164402581³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164402521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 317121 + ... + 317638.

It is an arithmetic number, because the mean of its divisors is an integer number (24120880).

Almost surely, 2^164402581 is an apocalyptic number.

It is an amenable number.

164402581 is a deficient number, since it is larger than the sum of its proper divisors (28564459).

164402581 is an equidigital number, since it uses as much as digits as its factorization.

164402581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 634803.

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 164402581 is about 12821.9569879173. The cubic root of 164402581 is about 547.8178895209.

The spelling of 164402581 in words is "one hundred sixty-four million, four hundred two thousand, five hundred eighty-one".