66544437 has 4 divisors (see below), whose sum is σ = 88725920. Its totient is φ = 44362956.

The previous prime is 66544397. The next prime is 66544459. The reversal of 66544437 is 73444566.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 66544437 - 2²⁰ = 65495861 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66544395 and 66544404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66544487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11090737 + ... + 11090742.

It is an arithmetic number, because the mean of its divisors is an integer number (22181480).

Almost surely, 2^66544437 is an apocalyptic number.

It is an amenable number.

66544437 is a deficient number, since it is larger than the sum of its proper divisors (22181483).

66544437 is a wasteful number, since it uses less digits than its factorization.

66544437 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22181482.

The product of its digits is 241920, while the sum is 39.

The square root of 66544437 is about 8157.4773674219. The cubic root of 66544437 is about 405.2321729285.

The spelling of 66544437 in words is "sixty-six million, five hundred forty-four thousand, four hundred thirty-seven".