66670388 has 6 divisors (see below), whose sum is σ = 116673186. Its totient is φ = 33335192.

The previous prime is 66670327. The next prime is 66670421. The reversal of 66670388 is 88307666.

It can be written as a sum of positive squares in only one way, i.e., 46076944 + 20593444 = 6788^2 + 4538^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8333795 + ... + 8333802.

It is an arithmetic number, because the mean of its divisors is an integer number (19445531).

Almost surely, 2^66670388 is an apocalyptic number.

It is an amenable number.

66670388 is a deficient number, since it is larger than the sum of its proper divisors (50002798).

66670388 is a wasteful number, since it uses less digits than its factorization.

66670388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16667601 (or 16667599 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 44.

The square root of 66670388 is about 8165.1936902930. The cubic root of 66670388 is about 405.4876775315.

The spelling of 66670388 in words is "sixty-six million, six hundred seventy thousand, three hundred eighty-eight".