66203181840 has 160 divisors (see below), whose sum is σ = 212663531520. Its totient is φ = 17025136128.

The previous prime is 66203181817. The next prime is 66203181857. The reversal of 66203181840 is 4818130266.

It is a super-2 number, since 2×66203181840² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 774679 + ... + 855881.

It is an arithmetic number, because the mean of its divisors is an integer number (1329147072).

Almost surely, 2^66203181840 is an apocalyptic number.

66203181840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66203181840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106331765760).

66203181840 is an abundant number, since it is smaller than the sum of its proper divisors (146460349680).

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

66203181840 is a wasteful number, since it uses less digits than its factorization.

66203181840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81341 (or 81335 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 39.

The spelling of 66203181840 in words is "sixty-six billion, two hundred three million, one hundred eighty-one thousand, eight hundred forty".