66678261833 has 4 divisors (see below), whose sum is σ = 67087331088. Its totient is φ = 66269192580.

The previous prime is 66678261809. The next prime is 66678261851. The reversal of 66678261833 is 33816287666.

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 a de Polignac number, because none of the positive numbers 2^k-66678261833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66678260833) 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, 204534383 + ... + 204534708.

It is an arithmetic number, because the mean of its divisors is an integer number (16771832772).

Almost surely, 2^66678261833 is an apocalyptic number.

It is an amenable number.

66678261833 is a deficient number, since it is larger than the sum of its proper divisors (409069255).

66678261833 is a wasteful number, since it uses less digits than its factorization.

66678261833 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409069254.

The product of its digits is 10450944, while the sum is 56.

The spelling of 66678261833 in words is "sixty-six billion, six hundred seventy-eight million, two hundred sixty-one thousand, eight hundred thirty-three".