66187198440 has 1152 divisors, whose sum is σ = 271445126400. Its totient is φ = 14301619200.

The previous prime is 66187198403. The next prime is 66187198471. The reversal of 66187198440 is 4489178166.

66187198440 is a `hidden beast` number, since 6 + 6 + 1 + 8 + 7 + 198 + 440 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 1085036010 + ... + 1085036070.

It is an arithmetic number, because the mean of its divisors is an integer number (235629450).

Almost surely, 2^66187198440 is an apocalyptic number.

66187198440 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 66187198440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135722563200).

66187198440 is an abundant number, since it is smaller than the sum of its proper divisors (205257927960).

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

66187198440 is a wasteful number, since it uses less digits than its factorization.

66187198440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 2322432, while the sum is 54.

The spelling of 66187198440 in words is "sixty-six billion, one hundred eighty-seven million, one hundred ninety-eight thousand, four hundred forty".