66131244 has 18 divisors (see below), whose sum is σ = 167165180. Its totient is φ = 22043736.

The previous prime is 66131239. The next prime is 66131249. The reversal of 66131244 is 44213166.

66131244 is a `hidden beast` number, since 6 + 613 + 1 + 2 + 44 = 666.

66131244 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (66131239) and next prime (66131249).

It is a tau number, because it is divible by the number of its divisors (18).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (66131249) 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 5 ways as a sum of consecutive naturals, for example, 918454 + ... + 918525.

Almost surely, 2^66131244 is an apocalyptic number.

It is an amenable number.

66131244 is an abundant number, since it is smaller than the sum of its proper divisors (101033936).

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

66131244 is a wasteful number, since it uses less digits than its factorization.

66131244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1836989 (or 1836984 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 66131244 is about 8132.1119028208. Note that the first 3 decimals coincide. The cubic root of 66131244 is about 404.3916976814.

The spelling of 66131244 in words is "sixty-six million, one hundred thirty-one thousand, two hundred forty-four".