1981571736 has 16 divisors (see below), whose sum is σ = 4953929400. Its totient is φ = 660523904.

The previous prime is 1981571719. The next prime is 1981571737. The reversal of 1981571736 is 6371751891.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1981571737) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41282721 + ... + 41282768.

Almost surely, 2^1981571736 is an apocalyptic number.

It is an amenable number.

1981571736 is an abundant number, since it is smaller than the sum of its proper divisors (2972357664).

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

1981571736 is a wasteful number, since it uses less digits than its factorization.

1981571736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82565498 (or 82565494 counting only the distinct ones).

The product of its digits is 317520, while the sum is 48.

The square root of 1981571736 is about 44514.8484890154. The cubic root of 1981571736 is about 1256.0394104366.

The spelling of 1981571736 in words is "one billion, nine hundred eighty-one million, five hundred seventy-one thousand, seven hundred thirty-six".