66401120 has 48 divisors (see below), whose sum is σ = 158669280. Its totient is φ = 26256384.

The previous prime is 66401119. The next prime is 66401171. The reversal of 66401120 is 2110466.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 66401092 and 66401101.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11909 + ... + 16571.

It is an arithmetic number, because the mean of its divisors is an integer number (3305610).

Almost surely, 2^66401120 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66401120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79334640).

66401120 is an abundant number, since it is smaller than the sum of its proper divisors (92268160).

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

66401120 is a wasteful number, since it uses less digits than its factorization.

66401120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4767 (or 4759 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 66401120 is about 8148.6882379927. The cubic root of 66401120 is about 404.9410471525.

Adding to 66401120 its reverse (2110466), we get a palindrome (68511586).

The spelling of 66401120 in words is "sixty-six million, four hundred one thousand, one hundred twenty".