66897829972 has 6 divisors (see below), whose sum is σ = 117071202458. Its totient is φ = 33448914984.

The previous prime is 66897829937. The next prime is 66897829981. The reversal of 66897829972 is 27992879866.

It can be written as a sum of positive squares in only one way, i.e., 62003988036 + 4893841936 = 249006^2 + 69956^2 .

It is a junction number, because it is equal to n+sod(n) for n = 66897829895 and 66897829904.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8362228743 + ... + 8362228750.

Almost surely, 2^66897829972 is an apocalyptic number.

It is an amenable number.

66897829972 is a deficient number, since it is larger than the sum of its proper divisors (50173372486).

66897829972 is a wasteful number, since it uses less digits than its factorization.

66897829972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16724457497 (or 16724457495 counting only the distinct ones).

The product of its digits is 329204736, while the sum is 73.

The spelling of 66897829972 in words is "sixty-six billion, eight hundred ninety-seven million, eight hundred twenty-nine thousand, nine hundred seventy-two".