66099172080 has 40 divisors (see below), whose sum is σ = 204907434192. Its totient is φ = 17626445824.

The previous prime is 66099172079. The next prime is 66099172093. The reversal of 66099172080 is 8027199066.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×66099172080² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (48).

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 in 7 ways as a sum of consecutive naturals, for example, 137706369 + ... + 137706848.

Almost surely, 2^66099172080 is an apocalyptic number.

66099172080 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66099172080 is an abundant number, since it is smaller than the sum of its proper divisors (138808262112).

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

66099172080 is a wasteful number, since it uses less digits than its factorization.

66099172080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275413233 (or 275413227 counting only the distinct ones).

The product of its (nonzero) digits is 326592, while the sum is 48.

The spelling of 66099172080 in words is "sixty-six billion, ninety-nine million, one hundred seventy-two thousand, eighty".