71664685 has 8 divisors (see below), whose sum is σ = 86088600. Its totient is φ = 57271104.

The previous prime is 71664661. The next prime is 71664709. The reversal of 71664685 is 58646617.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (71664661) and next prime (71664709).

It can be written as a sum of positive squares in 4 ways, for example, as 3337929 + 68326756 = 1827^2 + 8266^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 71664685 - 2¹³ = 71656493 is a prime.

It is a super-2 number, since 2×71664685² = 10271654152298450, which contains 22 as substring.

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, 2010 + ... + 12139.

It is an arithmetic number, because the mean of its divisors is an integer number (10761075).

Almost surely, 2^71664685 is an apocalyptic number.

It is an amenable number.

71664685 is a deficient number, since it is larger than the sum of its proper divisors (14423915).

71664685 is a wasteful number, since it uses less digits than its factorization.

71664685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15167.

The product of its digits is 241920, while the sum is 43.

The square root of 71664685 is about 8465.4996899179. The cubic root of 71664685 is about 415.3699415739.

The spelling of 71664685 in words is "seventy-one million, six hundred sixty-four thousand, six hundred eighty-five".