66813120 has 448 divisors, whose sum is σ = 277977600. Its totient is φ = 14929920.

The previous prime is 66813053. The next prime is 66813133. The reversal of 66813120 is 2131866.

It is a Harshad number since it is a multiple of its sum of digits (27).

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, 1805742 + ... + 1805778.

Almost surely, 2^66813120 is an apocalyptic number.

66813120 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 66813120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138988800).

66813120 is an abundant number, since it is smaller than the sum of its proper divisors (211164480).

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

66813120 is a wasteful number, since it uses less digits than its factorization.

66813120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 66813120 is about 8173.9292876804. The cubic root of 66813120 is about 405.7768354643.

Adding to 66813120 its reverse (2131866), we get a palindrome (68944986).

It can be divided in two parts, 6681 and 3120, that added together give a square (9801 = 99²).

The spelling of 66813120 in words is "sixty-six million, eight hundred thirteen thousand, one hundred twenty".