66440601 has 16 divisors (see below), whose sum is σ = 98723520. Its totient is φ = 44161920.

The previous prime is 66440597. The next prime is 66440609. The reversal of 66440601 is 10604466.

It is not a de Polignac number, because 66440601 - 2² = 66440597 is a prime.

It is a super-2 number, since 2×66440601² = 8828706922482402, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (66440609) 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 15 ways as a sum of consecutive naturals, for example, 6046 + ... + 13016.

It is an arithmetic number, because the mean of its divisors is an integer number (6170220).

Almost surely, 2^66440601 is an apocalyptic number.

It is an amenable number.

66440601 is a deficient number, since it is larger than the sum of its proper divisors (32282919).

66440601 is a wasteful number, since it uses less digits than its factorization.

66440601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7333 (or 7327 counting only the distinct ones).

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

The square root of 66440601 is about 8151.1104151520. The cubic root of 66440601 is about 405.0212883186.

The spelling of 66440601 in words is "sixty-six million, four hundred forty thousand, six hundred one".