67665780 has 384 divisors, whose sum is σ = 277724160. Its totient is φ = 13436928.

The previous prime is 67665751. The next prime is 67665781. The reversal of 67665780 is 8756676.

67665780 is a `hidden beast` number, since 6 + 76 + 6 + 578 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Saint-Exupery number, since it is equal to the product of the sides of a Pythagorean triangle: 765 × 117 × 756.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67665781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 3980332 + ... + 3980348.

It is an arithmetic number, because the mean of its divisors is an integer number (723240).

Almost surely, 2^67665780 is an apocalyptic number.

67665780 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 67665780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138862080).

67665780 is an abundant number, since it is smaller than the sum of its proper divisors (210058380).

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

67665780 is a wasteful number, since it uses less digits than its factorization.

67665780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 45.

The square root of 67665780 is about 8225.9212250057. The cubic root of 67665780 is about 407.4957004577.

The spelling of 67665780 in words is "sixty-seven million, six hundred sixty-five thousand, seven hundred eighty".