66664340 has 12 divisors (see below), whose sum is σ = 139995156. Its totient is φ = 26665728.

The previous prime is 66664321. The next prime is 66664349. The reversal of 66664340 is 4346666.

It can be written as a sum of positive squares in 2 ways, for example, as 50951044 + 15713296 = 7138^2 + 3964^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 66664340.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66664349) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1666589 + ... + 1666628.

It is an arithmetic number, because the mean of its divisors is an integer number (11666263).

Almost surely, 2^66664340 is an apocalyptic number.

It is an amenable number.

66664340 is an abundant number, since it is smaller than the sum of its proper divisors (73330816).

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

66664340 is a wasteful number, since it uses less digits than its factorization.

66664340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3333226 (or 3333224 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 35.

The square root of 66664340 is about 8164.8233293807. The cubic root of 66664340 is about 405.4754158978.

The spelling of 66664340 in words is "sixty-six million, six hundred sixty-four thousand, three hundred forty".