71311520 has 48 divisors (see below), whose sum is σ = 192544128. Its totient is φ = 24449280.

The previous prime is 71311489. The next prime is 71311529. The reversal of 71311520 is 2511317.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 71311492 and 71311501.

It is not an unprimeable number, because it can be changed into a prime (71311529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30716 + ... + 32955.

It is an arithmetic number, because the mean of its divisors is an integer number (4011336).

Almost surely, 2^71311520 is an apocalyptic number.

71311520 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

71311520 is an abundant number, since it is smaller than the sum of its proper divisors (121232608).

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

71311520 is a wasteful number, since it uses less digits than its factorization.

71311520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63693 (or 63685 counting only the distinct ones).

The product of its (nonzero) digits is 210, while the sum is 20.

The square root of 71311520 is about 8444.6148520818. The cubic root of 71311520 is about 414.6865005464.

Adding to 71311520 its reverse (2511317), we get a palindrome (73822837).

The spelling of 71311520 in words is "seventy-one million, three hundred eleven thousand, five hundred twenty".