1971821112 has 32 divisors (see below), whose sum is σ = 4933046400. Its totient is φ = 656807904.

The previous prime is 1971821107. The next prime is 1971821113. The reversal of 1971821112 is 2111281791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1971821113) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6339 + ... + 63117.

It is an arithmetic number, because the mean of its divisors is an integer number (154157700).

Almost surely, 2^1971821112 is an apocalyptic number.

1971821112 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1971821112 is an abundant number, since it is smaller than the sum of its proper divisors (2961225288).

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

1971821112 is a wasteful number, since it uses less digits than its factorization.

1971821112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58235 (or 58231 counting only the distinct ones).

The product of its digits is 2016, while the sum is 33.

The square root of 1971821112 is about 44405.1923990877. The cubic root of 1971821112 is about 1253.9758446135.

The spelling of 1971821112 in words is "one billion, nine hundred seventy-one million, eight hundred twenty-one thousand, one hundred twelve".