66869145 has 80 divisors (see below), whose sum is σ = 138927360. Its totient is φ = 30139776.

The previous prime is 66869141. The next prime is 66869191. The reversal of 66869145 is 54196866.

66869145 = 130² + 131² + ... + 587².

It is not a de Polignac number, because 66869145 - 2² = 66869141 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 66869145.

It is not an unprimeable number, because it can be changed into a prime (66869141) 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 79 ways as a sum of consecutive naturals, for example, 291891 + ... + 292119.

It is an arithmetic number, because the mean of its divisors is an integer number (1736592).

Almost surely, 2^66869145 is an apocalyptic number.

It is an amenable number.

66869145 is an abundant number, since it is smaller than the sum of its proper divisors (72058215).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66869145 is a wasteful number, since it uses less digits than its factorization.

66869145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356 (or 347 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The square root of 66869145 is about 8177.3556239166. The cubic root of 66869145 is about 405.8902228542.

The spelling of 66869145 in words is "sixty-six million, eight hundred sixty-nine thousand, one hundred forty-five".