1982897721 has 24 divisors (see below), whose sum is σ = 3276528320. Its totient is φ = 1131986016.

The previous prime is 1982897669. The next prime is 1982897729. The reversal of 1982897721 is 1277982891.

1982897721 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1982897721 - 2¹⁴ = 1982881337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1982897729) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 52626 + ... + 82068.

Almost surely, 2^1982897721 is an apocalyptic number.

It is an amenable number.

1982897721 is a deficient number, since it is larger than the sum of its proper divisors (1293630599).

1982897721 is a wasteful number, since it uses less digits than its factorization.

1982897721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30525 (or 30522 counting only the distinct ones).

The product of its digits is 1016064, while the sum is 54.

The square root of 1982897721 is about 44529.7397364952. The cubic root of 1982897721 is about 1256.3195109974.

The spelling of 1982897721 in words is "one billion, nine hundred eighty-two million, eight hundred ninety-seven thousand, seven hundred twenty-one".