66640735 has 12 divisors (see below), whose sum is σ = 93025368. Its totient is φ = 45696336.

The previous prime is 66640727. The next prime is 66640759. The reversal of 66640735 is 53704666.

It is not a de Polignac number, because 66640735 - 2³ = 66640727 is a prime.

It is a super-2 number, since 2×66640735² = 8881975122680450, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66640694 and 66640703.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 135757 + ... + 136246.

It is an arithmetic number, because the mean of its divisors is an integer number (7752114).

Almost surely, 2^66640735 is an apocalyptic number.

66640735 is a deficient number, since it is larger than the sum of its proper divisors (26384633).

66640735 is a wasteful number, since it uses less digits than its factorization.

66640735 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272022 (or 272015 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 37.

The square root of 66640735 is about 8163.3776710379. The cubic root of 66640735 is about 405.4275523419.

The spelling of 66640735 in words is "sixty-six million, six hundred forty thousand, seven hundred thirty-five".