66031420 has 144 divisors (see below), whose sum is σ = 178573248. Its totient is φ = 20321280.

The previous prime is 66031411. The next prime is 66031423. The reversal of 66031420 is 2413066.

It is a junction number, because it is equal to n+sod(n) for n = 66031391 and 66031400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66031423) 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, 904504 + ... + 904576.

It is an arithmetic number, because the mean of its divisors is an integer number (1240092).

Almost surely, 2^66031420 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 66031420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89286624).

66031420 is an abundant number, since it is smaller than the sum of its proper divisors (112541828).

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

66031420 is a wasteful number, since it uses less digits than its factorization.

66031420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180 (or 171 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 66031420 is about 8125.9719418664. The cubic root of 66031420 is about 404.1881210609.

Adding to 66031420 its reverse (2413066), we get a palindrome (68444486).

The spelling of 66031420 in words is "sixty-six million, thirty-one thousand, four hundred twenty".