66779411811840 has 480 divisors, whose sum is σ = 284647251784896. Its totient is φ = 14089721610240.

The previous prime is 66779411811799. The next prime is 66779411811841. The reversal of 66779411811840 is 4811811497766.

66779411811840 is a `hidden beast` number, since 6 + 67 + 7 + 9 + 411 + 8 + 118 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66779411811841) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13828701 + ... + 18021980.

Almost surely, 2^{66779411811840} is an apocalyptic number.

66779411811840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66779411811840 is an abundant number, since it is smaller than the sum of its proper divisors (217867839973056).

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

66779411811840 is a wasteful number, since it uses less digits than its factorization.

66779411811840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31850730 (or 31850711 counting only the distinct ones).

The product of its (nonzero) digits is 16257024, while the sum is 63.

The spelling of 66779411811840 in words is "sixty-six trillion, seven hundred seventy-nine billion, four hundred eleven million, eight hundred eleven thousand, eight hundred forty".