71515840 has 84 divisors (see below), whose sum is σ = 187287408. Its totient is φ = 25991680.

The previous prime is 71515819. The next prime is 71515841. The reversal of 71515840 is 4851517.

It is a super-2 number, since 2×71515840² = 10229030741811200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (71515841) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 37797 + ... + 39643.

It is an arithmetic number, because the mean of its divisors is an integer number (2229612).

Almost surely, 2^71515840 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 71515840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93643704).

71515840 is an abundant number, since it is smaller than the sum of its proper divisors (115771568).

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

71515840 is a wasteful number, since it uses less digits than its factorization.

71515840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1886 (or 1865 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 31.

The square root of 71515840 is about 8456.7038496095. The cubic root of 71515840 is about 415.0821727251.

The spelling of 71515840 in words is "seventy-one million, five hundred fifteen thousand, eight hundred forty".