66264868081 has 4 divisors (see below), whose sum is σ = 66265388352. Its totient is φ = 66264347812.

The previous prime is 66264868067. The next prime is 66264868099. The reversal of 66264868081 is 18086846266.

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 66264868081 - 2⁹ = 66264867569 is a prime.

It is a super-2 number, since 2×66264868081² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66264868051) 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, 73836 + ... + 371458.

It is an arithmetic number, because the mean of its divisors is an integer number (16566347088).

Almost surely, 2^66264868081 is an apocalyptic number.

It is an amenable number.

66264868081 is a deficient number, since it is larger than the sum of its proper divisors (520271).

66264868081 is a wasteful number, since it uses less digits than its factorization.

66264868081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 520270.

The product of its (nonzero) digits is 5308416, while the sum is 55.

The spelling of 66264868081 in words is "sixty-six billion, two hundred sixty-four million, eight hundred sixty-eight thousand, eighty-one".