66445501 has 4 divisors (see below), whose sum is σ = 66489472. Its totient is φ = 66401532.

The previous prime is 66445499. The next prime is 66445513. The reversal of 66445501 is 10554466.

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 a cyclic number.

It is not a de Polignac number, because 66445501 - 2¹ = 66445499 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66445591) 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, 19635 + ... + 22768.

It is an arithmetic number, because the mean of its divisors is an integer number (16622368).

Almost surely, 2^66445501 is an apocalyptic number.

It is an amenable number.

66445501 is a deficient number, since it is larger than the sum of its proper divisors (43971).

66445501 is a wasteful number, since it uses less digits than its factorization.

66445501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43970.

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 66445501 is about 8151.4109821552. The cubic root of 66445501 is about 405.0312448587.

Adding to 66445501 its reverse (10554466), we get a palindrome (76999967).

The spelling of 66445501 in words is "sixty-six million, four hundred forty-five thousand, five hundred one".