66733685538840 has 128 divisors (see below), whose sum is σ = 223032547584000. Its totient is φ = 17748695147904.

The previous prime is 66733685538829. The next prime is 66733685538857. The reversal of 66733685538840 is 4883558633766.

66733685538840 is a `hidden beast` number, since 6 + 6 + 7 + 3 + 3 + 6 + 8 + 5 + 538 + 84 + 0 = 666.

It is a super-3 number, since 3×66733685538840³ (a number of 42 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

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, 81108424 + ... + 81927063.

It is an arithmetic number, because the mean of its divisors is an integer number (1742441778000).

Almost surely, 2^{66733685538840} is an apocalyptic number.

66733685538840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66733685538840 is an abundant number, since it is smaller than the sum of its proper divisors (156298862045160).

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

66733685538840 is a wasteful number, since it uses less digits than its factorization.

66733685538840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163035886 (or 163035876 counting only the distinct ones).

The product of its (nonzero) digits is 2090188800, while the sum is 72.

The spelling of 66733685538840 in words is "sixty-six trillion, seven hundred thirty-three billion, six hundred eighty-five million, five hundred thirty-eight thousand, eight hundred forty".