64071166261 has 4 divisors (see below), whose sum is σ = 67840058412. Its totient is φ = 60302274112.

The previous prime is 64071166199. The next prime is 64071166277. The reversal of 64071166261 is 16266117046.

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 32483213361 + 31587952900 = 180231^2 + 177730^2 .

It is a cyclic number.

It is not a de Polignac number, because 64071166261 - 2⁹ = 64071165749 is a prime.

It is a super-2 number, since 2×64071166261² (a number of 22 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 (64071166961) 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, 1884446050 + ... + 1884446083.

It is an arithmetic number, because the mean of its divisors is an integer number (16960014603).

Almost surely, 2^64071166261 is an apocalyptic number.

It is an amenable number.

64071166261 is a deficient number, since it is larger than the sum of its proper divisors (3768892151).

64071166261 is a wasteful number, since it uses less digits than its factorization.

64071166261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3768892150.

The product of its (nonzero) digits is 72576, while the sum is 40.

The spelling of 64071166261 in words is "sixty-four billion, seventy-one million, one hundred sixty-six thousand, two hundred sixty-one".