66678261831 has 16 divisors (see below), whose sum is σ = 100135799520. Its totient is φ = 43843239360.

The previous prime is 66678261809. The next prime is 66678261851. The reversal of 66678261831 is 13816287666.

It is not a de Polignac number, because 66678261831 - 2⁷ = 66678261703 is a prime.

It is a super-2 number, since 2×66678261831² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66678261851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16912860 + ... + 16916801.

It is an arithmetic number, because the mean of its divisors is an integer number (6258487470).

Almost surely, 2^66678261831 is an apocalyptic number.

66678261831 is a deficient number, since it is larger than the sum of its proper divisors (33457537689).

66678261831 is a wasteful number, since it uses less digits than its factorization.

66678261831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33829743 (or 33829737 counting only the distinct ones).

The product of its digits is 3483648, while the sum is 54.

It can be divided in two parts, 66678 and 261831, that added together give a cube (328509 = 69³).

The spelling of 66678261831 in words is "sixty-six billion, six hundred seventy-eight million, two hundred sixty-one thousand, eight hundred thirty-one".