66149909 has 16 divisors (see below), whose sum is σ = 79419648. Its totient is φ = 53868672.

The previous prime is 66149903. The next prime is 66149947. The reversal of 66149909 is 90994166.

It is a cyclic number.

It is not a de Polignac number, because 66149909 - 2⁴ = 66149893 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66149909.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66149903) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23969 + ... + 26585.

It is an arithmetic number, because the mean of its divisors is an integer number (4963728).

Almost surely, 2^66149909 is an apocalyptic number.

It is an amenable number.

66149909 is a deficient number, since it is larger than the sum of its proper divisors (13269739).

66149909 is a wasteful number, since it uses less digits than its factorization.

66149909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2804.

The product of its (nonzero) digits is 104976, while the sum is 44.

The square root of 66149909 is about 8133.2594327244. The cubic root of 66149909 is about 404.4297395134.

The spelling of 66149909 in words is "sixty-six million, one hundred forty-nine thousand, nine hundred nine".