66540458880 has 512 divisors, whose sum is σ = 285182208000. Its totient is φ = 14314143744.

The previous prime is 66540458879. The next prime is 66540458909. The reversal of 66540458880 is 8885404566.

66540458880 is a `hidden beast` number, since 6 + 6 + 54 + 0 + 4 + 588 + 8 + 0 = 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 63 ways as a sum of consecutive naturals, for example, 2040141 + ... + 2072499.

It is an arithmetic number, because the mean of its divisors is an integer number (556996500).

Almost surely, 2^66540458880 is an apocalyptic number.

66540458880 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 66540458880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142591104000).

66540458880 is an abundant number, since it is smaller than the sum of its proper divisors (218641749120).

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

66540458880 is a wasteful number, since it uses less digits than its factorization.

66540458880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32411 (or 32393 counting only the distinct ones).

The product of its (nonzero) digits is 7372800, while the sum is 54.

The spelling of 66540458880 in words is "sixty-six billion, five hundred forty million, four hundred fifty-eight thousand, eight hundred eighty".