66905345 has 16 divisors (see below), whose sum is σ = 88098192. Its totient is φ = 48472320.

The previous prime is 66905341. The next prime is 66905381. The reversal of 66905345 is 54350966.

It can be written as a sum of positive squares in 8 ways, for example, as 1893376 + 65011969 = 1376^2 + 8063^2 .

It is not a de Polignac number, because 66905345 - 2² = 66905341 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66905299 and 66905308.

It is not an unprimeable number, because it can be changed into a prime (66905341) 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, 6266 + ... + 13155.

It is an arithmetic number, because the mean of its divisors is an integer number (5506137).

Almost surely, 2^66905345 is an apocalyptic number.

66905345 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66905345 is a deficient number, since it is larger than the sum of its proper divisors (21192847).

66905345 is a wasteful number, since it uses less digits than its factorization.

66905345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19492.

The product of its (nonzero) digits is 97200, while the sum is 38.

The square root of 66905345 is about 8179.5687539136. The cubic root of 66905345 is about 405.9634533177.

The spelling of 66905345 in words is "sixty-six million, nine hundred five thousand, three hundred forty-five".