66666670 has 16 divisors (see below), whose sum is σ = 137143008. Its totient is φ = 22857120.

The previous prime is 66666667. The next prime is 66666683. The reversal of 66666670 is 7666666.

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, 476121 + ... + 476260.

It is an arithmetic number, because the mean of its divisors is an integer number (8571438).

Almost surely, 2^66666670 is an apocalyptic number.

66666670 is an abundant number, since it is smaller than the sum of its proper divisors (70476338).

66666670 is a wasteful number, since it uses less digits than its factorization.

66666670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 952395.

The product of its (nonzero) digits is 326592, while the sum is 43.

The square root of 66666670 is about 8164.9660134014. The cubic root of 66666670 is about 405.4801397962.

The spelling of 66666670 in words is "sixty-six million, six hundred sixty-six thousand, six hundred seventy".