66212288831 has 4 divisors (see below), whose sum is σ = 71305541832. Its totient is φ = 61119035832.

The previous prime is 66212288783. The next prime is 66212288869. The reversal of 66212288831 is 13888221266.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66212288831 is a prime.

It is a super-2 number, since 2×66212288831² (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 (66212278831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2546626481 + ... + 2546626506.

It is an arithmetic number, because the mean of its divisors is an integer number (17826385458).

Almost surely, 2^66212288831 is an apocalyptic number.

66212288831 is a deficient number, since it is larger than the sum of its proper divisors (5093253001).

66212288831 is a wasteful number, since it uses less digits than its factorization.

66212288831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5093253000.

The product of its digits is 442368, while the sum is 47.

The spelling of 66212288831 in words is "sixty-six billion, two hundred twelve million, two hundred eighty-eight thousand, eight hundred thirty-one".