9897887989 has 4 divisors (see below), whose sum is σ = 10797696000. Its totient is φ = 8998079980.

The previous prime is 9897887981. The next prime is 9897888017.

9897887989 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 9897887989 - 2³ = 9897887981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9897887981) 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, 449903989 + ... + 449904010.

It is an arithmetic number, because the mean of its divisors is an integer number (2699424000).

Almost surely, 2^9897887989 is an apocalyptic number.

It is an amenable number.

9897887989 is a deficient number, since it is larger than the sum of its proper divisors (899808011).

9897887989 is a wasteful number, since it uses less digits than its factorization.

9897887989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 899808010.

The product of its digits is 1316818944, while the sum is 82.

The square root of 9897887989 is about 99488.1298899522. The cubic root of 9897887989 is about 2147.0764655122.

The spelling of 9897887989 in words is "nine billion, eight hundred ninety-seven million, eight hundred eighty-seven thousand, nine hundred eighty-nine".