66172133317720 has 16 divisors (see below), whose sum is σ = 148887299964960. Its totient is φ = 26468853327072.

The previous prime is 66172133317711. The next prime is 66172133317729. The reversal of 66172133317720 is 2771333127166.

It is an interprime number because it is at equal distance from previous prime (66172133317711) and next prime (66172133317729).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66172133317729) 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, 827151666432 + ... + 827151666511.

It is an arithmetic number, because the mean of its divisors is an integer number (9305456247810).

Almost surely, 2^{66172133317720} is an apocalyptic number.

It is an amenable number.

66172133317720 is an abundant number, since it is smaller than the sum of its proper divisors (82715166647240).

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

66172133317720 is a wasteful number, since it uses less digits than its factorization.

66172133317720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1654303332954 (or 1654303332950 counting only the distinct ones).

The product of its (nonzero) digits is 1333584, while the sum is 49.

The spelling of 66172133317720 in words is "sixty-six trillion, one hundred seventy-two billion, one hundred thirty-three million, three hundred seventeen thousand, seven hundred twenty".