66918710 has 16 divisors (see below), whose sum is σ = 120548736. Its totient is φ = 26746368.

The previous prime is 66918673. The next prime is 66918721. The reversal of 66918710 is 1781966.

It is a super-2 number, since 2×66918710² = 8956227496128200, which contains 22 as substring.

It is a Curzon number.

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, 19547 + ... + 22713.

It is an arithmetic number, because the mean of its divisors is an integer number (7534296).

Almost surely, 2^66918710 is an apocalyptic number.

66918710 is a deficient number, since it is larger than the sum of its proper divisors (53630026).

66918710 is a wasteful number, since it uses less digits than its factorization.

66918710 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5287.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 66918710 is about 8180.3856877289. The cubic root of 66918710 is about 405.9904832474.

The spelling of 66918710 in words is "sixty-six million, nine hundred eighteen thousand, seven hundred ten".