71218728 has 48 divisors (see below), whose sum is σ = 220440480. Its totient is φ = 20348064.

The previous prime is 71218709. The next prime is 71218733. The reversal of 71218728 is 82781217.

It is a happy number.

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

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 71218692 and 71218701.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 70150 + ... + 71157.

It is an arithmetic number, because the mean of its divisors is an integer number (4592510).

Almost surely, 2^71218728 is an apocalyptic number.

It is an amenable number.

71218728 is an abundant number, since it is smaller than the sum of its proper divisors (149221752).

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

71218728 is a wasteful number, since it uses less digits than its factorization.

71218728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141326 (or 141319 counting only the distinct ones).

The product of its digits is 12544, while the sum is 36.

The square root of 71218728 is about 8439.1189113556. The cubic root of 71218728 is about 414.5065563057.

The spelling of 71218728 in words is "seventy-one million, two hundred eighteen thousand, seven hundred twenty-eight".