164457581 has 4 divisors (see below), whose sum is σ = 164492352. Its totient is φ = 164422812.

The previous prime is 164457577. The next prime is 164457607. The reversal of 164457581 is 185754461.

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.

It is a cyclic number.

It is not a de Polignac number, because 164457581 - 2² = 164457577 is a prime.

It is a super-2 number, since 2×164457581² = 54092591896743122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164457481) 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, 8915 + ... + 20208.

It is an arithmetic number, because the mean of its divisors is an integer number (41123088).

Almost surely, 2^164457581 is an apocalyptic number.

It is an amenable number.

164457581 is a deficient number, since it is larger than the sum of its proper divisors (34771).

164457581 is an equidigital number, since it uses as much as digits as its factorization.

164457581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34770.

The product of its digits is 134400, while the sum is 41.

The square root of 164457581 is about 12824.1015669715. The cubic root of 164457581 is about 547.8789725534.

The spelling of 164457581 in words is "one hundred sixty-four million, four hundred fifty-seven thousand, five hundred eighty-one".