71847720 has 144 divisors (see below), whose sum is σ = 271695060. Its totient is φ = 16418304.

The previous prime is 71847719. The next prime is 71847749. The reversal of 71847720 is 2774817.

It can be written as a sum of positive squares in 2 ways, for example, as 65707236 + 6140484 = 8106^2 + 2478^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 15604 + ... + 19676.

Almost surely, 2^71847720 is an apocalyptic number.

71847720 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71847720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135847530).

71847720 is an abundant number, since it is smaller than the sum of its proper divisors (199847340).

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

71847720 is a wasteful number, since it uses less digits than its factorization.

71847720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4104 (or 4090 counting only the distinct ones).

The product of its (nonzero) digits is 21952, while the sum is 36.

The square root of 71847720 is about 8476.3034395897. The cubic root of 71847720 is about 415.7232657773.

The spelling of 71847720 in words is "seventy-one million, eight hundred forty-seven thousand, seven hundred twenty".