71999856 has 90 divisors (see below), whose sum is σ = 209650272. Its totient is φ = 23042880.

The previous prime is 71999849. The next prime is 71999857. The reversal of 71999856 is 65899917.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71999857) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 566865 + ... + 566991.

Almost surely, 2^71999856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71999856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104825136).

71999856 is an abundant number, since it is smaller than the sum of its proper divisors (137650416).

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

71999856 is a wasteful number, since it uses less digits than its factorization.

71999856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299 (or 163 counting only the distinct ones).

The product of its digits is 1224720, while the sum is 54.

The square root of 71999856 is about 8485.2728889530. The cubic root of 71999856 is about 416.0164872657.

The spelling of 71999856 in words is "seventy-one million, nine hundred ninety-nine thousand, eight hundred fifty-six".