971991228 has 48 divisors (see below), whose sum is σ = 2458674176. Its totient is φ = 297086400.

The previous prime is 971991211. The next prime is 971991233. The reversal of 971991228 is 822199179.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2925 + ... + 44187.

Almost surely, 2^971991228 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 971991228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1229337088).

971991228 is an abundant number, since it is smaller than the sum of its proper divisors (1486682948).

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

971991228 is a wasteful number, since it uses less digits than its factorization.

971991228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41434 (or 41432 counting only the distinct ones).

The product of its digits is 163296, while the sum is 48.

The square root of 971991228 is about 31176.7738549068. The cubic root of 971991228 is about 990.5751947720.

The spelling of 971991228 in words is "nine hundred seventy-one million, nine hundred ninety-one thousand, two hundred twenty-eight".