66665296 has 40 divisors (see below), whose sum is σ = 137837160. Its totient is φ = 31125504.

The previous prime is 66665273. The next prime is 66665311. The reversal of 66665296 is 69256666.

It can be written as a sum of positive squares in 4 ways, for example, as 38192400 + 28472896 = 6180^2 + 5336^2 .

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36370 + ... + 38158.

It is an arithmetic number, because the mean of its divisors is an integer number (3445929).

Almost surely, 2^66665296 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66665296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68918580).

66665296 is an abundant number, since it is smaller than the sum of its proper divisors (71171864).

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

66665296 is a wasteful number, since it uses less digits than its factorization.

66665296 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1951 (or 1945 counting only the distinct ones).

The product of its digits is 699840, while the sum is 46.

The square root of 66665296 is about 8164.8818729973. The cubic root of 66665296 is about 405.4773541287.

The spelling of 66665296 in words is "sixty-six million, six hundred sixty-five thousand, two hundred ninety-six".