70656709 has 4 divisors (see below), whose sum is σ = 74813004. Its totient is φ = 66500416.

The previous prime is 70656679. The next prime is 70656737. The reversal of 70656709 is 90765607.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90765607 = 2221 ⋅40867.

It can be written as a sum of positive squares in 2 ways, for example, as 26061025 + 44595684 = 5105^2 + 6678^2 .

It is a cyclic number.

It is not a de Polignac number, because 70656709 - 2⁷ = 70656581 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70656749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2078122 + ... + 2078155.

It is an arithmetic number, because the mean of its divisors is an integer number (18703251).

Almost surely, 2^70656709 is an apocalyptic number.

It is an amenable number.

70656709 is a deficient number, since it is larger than the sum of its proper divisors (4156295).

70656709 is a wasteful number, since it uses less digits than its factorization.

70656709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4156294.

The product of its (nonzero) digits is 79380, while the sum is 40.

The square root of 70656709 is about 8405.7545169961. The cubic root of 70656709 is about 413.4133229831.

The spelling of 70656709 in words is "seventy million, six hundred fifty-six thousand, seven hundred nine".