71669911 has 4 divisors (see below), whose sum is σ = 72304272. Its totient is φ = 71035552.

The previous prime is 71669891. The next prime is 71669947. The reversal of 71669911 is 11996617.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71669911 is a prime.

It is a super-2 number, since 2×71669911² = 10273152285495842, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71669951) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 317011 + ... + 317236.

It is an arithmetic number, because the mean of its divisors is an integer number (18076068).

Almost surely, 2^71669911 is an apocalyptic number.

71669911 is a deficient number, since it is larger than the sum of its proper divisors (634361).

71669911 is a wasteful number, since it uses less digits than its factorization.

71669911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 634360.

The product of its digits is 20412, while the sum is 40.

The square root of 71669911 is about 8465.8083488820. The cubic root of 71669911 is about 415.3800379952.

The spelling of 71669911 in words is "seventy-one million, six hundred sixty-nine thousand, nine hundred eleven".