971831520 has 480 divisors, whose sum is σ = 3971522016. Its totient is φ = 221184000.

The previous prime is 971831507. The next prime is 971831521. The reversal of 971831520 is 25138179.

971831520 is a `hidden beast` number, since 97 + 18 + 31 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (971831521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2423320 + ... + 2423720.

Almost surely, 2^971831520 is an apocalyptic number.

971831520 is a gapful number since it is divisible by the number (90) 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 971831520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1985761008).

971831520 is an abundant number, since it is smaller than the sum of its proper divisors (2999690496).

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

971831520 is a wasteful number, since it uses less digits than its factorization.

971831520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 456 (or 439 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 971831520 is about 31174.2124198832. The cubic root of 971831520 is about 990.5209379556.

Adding to 971831520 its reverse (25138179), we get a palindrome (996969699).

The spelling of 971831520 in words is "nine hundred seventy-one million, eight hundred thirty-one thousand, five hundred twenty".