71521112 has 32 divisors (see below), whose sum is σ = 146059200. Its totient is φ = 32634624.

The previous prime is 71521103. The next prime is 71521127. The reversal of 71521112 is 21112517.

71521112 = T₁₂₂₃ + T₁₂₂₄ + ... + T₁₃₁₁.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5393 + ... + 13119.

It is an arithmetic number, because the mean of its divisors is an integer number (4564350).

Almost surely, 2^71521112 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 71521112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73029600).

71521112 is an abundant number, since it is smaller than the sum of its proper divisors (74538088).

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

71521112 is a wasteful number, since it uses less digits than its factorization.

71521112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7835 (or 7831 counting only the distinct ones).

The product of its digits is 140, while the sum is 20.

The square root of 71521112 is about 8457.0155492348. The cubic root of 71521112 is about 415.0923721413.

Adding to 71521112 its reverse (21112517), we get a palindrome (92633629).

The spelling of 71521112 in words is "seventy-one million, five hundred twenty-one thousand, one hundred twelve".