66784279965120 has 392 divisors, whose sum is σ = 238527978451344. Its totient is φ = 17802273374208.

The previous prime is 66784279965101. The next prime is 66784279965131. The reversal of 66784279965120 is 2156997248766.

66784279965120 is a `hidden beast` number, since 6 + 6 + 7 + 84 + 27 + 9 + 9 + 6 + 512 + 0 = 666.

It is a super-2 number, since 2×66784279965120² (a number of 28 digits) contains 22 as substring.

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 55 ways as a sum of consecutive naturals, for example, 619771087 + ... + 619878833.

Almost surely, 2^{66784279965120} is an apocalyptic number.

66784279965120 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 66784279965120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119263989225672).

66784279965120 is an abundant number, since it is smaller than the sum of its proper divisors (171743698486224).

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

66784279965120 is a wasteful number, since it uses less digits than its factorization.

66784279965120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110439 (or 110414 counting only the distinct ones).

The product of its (nonzero) digits is 548674560, while the sum is 72.

The spelling of 66784279965120 in words is "sixty-six trillion, seven hundred eighty-four billion, two hundred seventy-nine million, nine hundred sixty-five thousand, one hundred twenty".