164241953581 has 4 divisors (see below), whose sum is σ = 164243245852. Its totient is φ = 164240661312.

The previous prime is 164241953567. The next prime is 164241953599. The reversal of 164241953581 is 185359142461.

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

It can be written as a sum of positive squares in 2 ways, for example, as 78703252681 + 85538700900 = 280541^2 + 292470^2 .

It is a cyclic number.

It is not a de Polignac number, because 164241953581 - 2¹⁹ = 164241429293 is a prime.

It is a super-2 number, since 2×164241953581² (a number of 23 digits) 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 (164241953881) 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, 431790 + ... + 717583.

It is an arithmetic number, because the mean of its divisors is an integer number (41060811463).

Almost surely, 2^164241953581 is an apocalyptic number.

It is an amenable number.

164241953581 is a deficient number, since it is larger than the sum of its proper divisors (1292271).

164241953581 is a wasteful number, since it uses less digits than its factorization.

164241953581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1292270.

The product of its digits is 1036800, while the sum is 49.

The spelling of 164241953581 in words is "one hundred sixty-four billion, two hundred forty-one million, nine hundred fifty-three thousand, five hundred eighty-one".