66975439 has 16 divisors (see below), whose sum is σ = 70594272. Its totient is φ = 63479808.

The previous prime is 66975397. The next prime is 66975449. The reversal of 66975439 is 93457966.

It is a cyclic number.

It is not a de Polignac number, because 66975439 - 2¹⁷ = 66844367 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66975392 and 66975401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66975449) 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, 346927 + ... + 347119.

It is an arithmetic number, because the mean of its divisors is an integer number (4412142).

Almost surely, 2^66975439 is an apocalyptic number.

66975439 is a deficient number, since it is larger than the sum of its proper divisors (3618833).

66975439 is a wasteful number, since it uses less digits than its factorization.

66975439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426.

The product of its digits is 1224720, while the sum is 49.

The square root of 66975439 is about 8183.8523324899. The cubic root of 66975439 is about 406.1051742859.

The spelling of 66975439 in words is "sixty-six million, nine hundred seventy-five thousand, four hundred thirty-nine".