66787172100 has 162 divisors, whose sum is σ = 230102114970. Its totient is φ = 16190803200.

The previous prime is 66787172087. The next prime is 66787172267. The reversal of 66787172100 is 127178766.

It can be written as a sum of positive squares in 3 ways, for example, as 8944998084 + 57842174016 = 94578^2 + 240504^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

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 in 53 ways as a sum of consecutive naturals, for example, 197745 + ... + 415544.

Almost surely, 2^66787172100 is an apocalyptic number.

66787172100 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66787172100 is an abundant number, since it is smaller than the sum of its proper divisors (163314942870).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66787172100 is a wasteful number, since it uses less digits than its factorization.

66787172100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 613331 (or 613310 counting only the distinct ones).

The product of its (nonzero) digits is 197568, while the sum is 45.

The spelling of 66787172100 in words is "sixty-six billion, seven hundred eighty-seven million, one hundred seventy-two thousand, one hundred".