1983897621 has 6 divisors (see below), whose sum is σ = 2865629910. Its totient is φ = 1322598408.

The previous prime is 1983897611. The next prime is 1983897647. The reversal of 1983897621 is 1267983891.

1983897621 is a `hidden beast` number, since 1 + 9 + 8 + 3 + 8 + 9 + 7 + 621 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1908728721 + 75168900 = 43689^2 + 8670^2 .

It is not a de Polignac number, because 1983897621 - 2⁶ = 1983897557 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1983897611) 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 5 ways as a sum of consecutive naturals, for example, 110216526 + ... + 110216543.

It is an arithmetic number, because the mean of its divisors is an integer number (477604985).

Almost surely, 2^1983897621 is an apocalyptic number.

It is an amenable number.

1983897621 is a deficient number, since it is larger than the sum of its proper divisors (881732289).

1983897621 is a wasteful number, since it uses less digits than its factorization.

1983897621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220433075 (or 220433072 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 54.

The square root of 1983897621 is about 44540.9656496129. The cubic root of 1983897621 is about 1256.5306469148.

The spelling of 1983897621 in words is "one billion, nine hundred eighty-three million, eight hundred ninety-seven thousand, six hundred twenty-one".