66374581 has 24 divisors (see below), whose sum is σ = 86493120. Its totient is φ = 49735296.

The previous prime is 66374557. The next prime is 66374597. The reversal of 66374581 is 18547366.

It is a happy number.

It is not a de Polignac number, because 66374581 - 2¹³ = 66366389 is a prime.

It is a super-2 number, since 2×66374581² = 8811170005851122, which contains 22 as substring.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66374521) 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 23 ways as a sum of consecutive naturals, for example, 21001 + ... + 23953.

It is an arithmetic number, because the mean of its divisors is an integer number (3603880).

Almost surely, 2^66374581 is an apocalyptic number.

It is an amenable number.

66374581 is a deficient number, since it is larger than the sum of its proper divisors (20118539).

66374581 is a wasteful number, since it uses less digits than its factorization.

66374581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3005 (or 2992 counting only the distinct ones).

The product of its digits is 120960, while the sum is 40.

The square root of 66374581 is about 8147.0596536419. The cubic root of 66374581 is about 404.8870914235.

The spelling of 66374581 in words is "sixty-six million, three hundred seventy-four thousand, five hundred eighty-one".