9897557988 has 24 divisors (see below), whose sum is σ = 23318521408. Its totient is φ = 3267154656.

The previous prime is 9897557959. The next prime is 9897557993. The reversal of 9897557988 is 8897557989.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4002631 + ... + 4005102.

Almost surely, 2^9897557988 is an apocalyptic number.

It is an amenable number.

9897557988 is an abundant number, since it is smaller than the sum of its proper divisors (13420963420).

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

9897557988 is a wasteful number, since it uses less digits than its factorization.

9897557988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8007843 (or 8007841 counting only the distinct ones).

The product of its digits is 457228800, while the sum is 75.

The square root of 9897557988 is about 99486.4713817914. The cubic root of 9897557988 is about 2147.0526036790.

Subtracting from 9897557988 its reverse (8897557989), we obtain a palindrome (999999999).

The spelling of 9897557988 in words is "nine billion, eight hundred ninety-seven million, five hundred fifty-seven thousand, nine hundred eighty-eight".