1989797013 has 6 divisors (see below), whose sum is σ = 2874151254. Its totient is φ = 1326531336.

The previous prime is 1989797009. The next prime is 1989797023. The reversal of 1989797013 is 3107979891.

It can be written as a sum of positive squares in only one way, i.e., 1988981604 + 815409 = 44598^2 + 903^2 .

It is not a de Polignac number, because 1989797013 - 2² = 1989797009 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1989797023) 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, 110544270 + ... + 110544287.

It is an arithmetic number, because the mean of its divisors is an integer number (479025209).

Almost surely, 2^1989797013 is an apocalyptic number.

It is an amenable number.

1989797013 is a deficient number, since it is larger than the sum of its proper divisors (884354241).

1989797013 is a wasteful number, since it uses less digits than its factorization.

1989797013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221088563 (or 221088560 counting only the distinct ones).

The product of its (nonzero) digits is 857304, while the sum is 54.

The square root of 1989797013 is about 44607.1408296923. The cubic root of 1989797013 is about 1257.7749032137.

The spelling of 1989797013 in words is "one billion, nine hundred eighty-nine million, seven hundred ninety-seven thousand, thirteen".