71805690 has 80 divisors (see below), whose sum is σ = 210656160. Its totient is φ = 17405280.

The previous prime is 71805683. The next prime is 71805733. The reversal of 71805690 is 9650817.

It is a super-2 number, since 2×71805690² = 10312114232752200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4881 + ... + 12939.

It is an arithmetic number, because the mean of its divisors is an integer number (2633202).

Almost surely, 2^71805690 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71805690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105328080).

71805690 is an abundant number, since it is smaller than the sum of its proper divisors (138850470).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

71805690 is a wasteful number, since it uses less digits than its factorization.

71805690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8089 (or 8080 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 71805690 is about 8473.8238121877. The cubic root of 71805690 is about 415.6421856952.

The spelling of 71805690 in words is "seventy-one million, eight hundred five thousand, six hundred ninety".