66688695 has 12 divisors (see below), whose sum is σ = 115593816. Its totient is φ = 35567280.

The previous prime is 66688691. The next prime is 66688717. The reversal of 66688695 is 59688666.

It is not a de Polignac number, because 66688695 - 2² = 66688691 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66688691) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 740941 + ... + 741030.

It is an arithmetic number, because the mean of its divisors is an integer number (9632818).

Almost surely, 2^66688695 is an apocalyptic number.

66688695 is a deficient number, since it is larger than the sum of its proper divisors (48905121).

66688695 is a wasteful number, since it uses less digits than its factorization.

66688695 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1481982 (or 1481979 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 54.

The square root of 66688695 is about 8166.3146522774. The cubic root of 66688695 is about 405.5247883778.

The spelling of 66688695 in words is "sixty-six million, six hundred eighty-eight thousand, six hundred ninety-five".