989556647 has 4 divisors (see below), whose sum is σ = 1023679320. Its totient is φ = 955433976.

The previous prime is 989556641. The next prime is 989556649. The reversal of 989556647 is 746655989.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 989556647 - 2²⁰ = 988508071 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 (989556641) 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, 17061293 + ... + 17061350.

It is an arithmetic number, because the mean of its divisors is an integer number (255919830).

Almost surely, 2^989556647 is an apocalyptic number.

989556647 is a deficient number, since it is larger than the sum of its proper divisors (34122673).

989556647 is a wasteful number, since it uses less digits than its factorization.

989556647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34122672.

The product of its digits is 16329600, while the sum is 59.

The square root of 989556647 is about 31457.2193144912. The cubic root of 989556647 is about 996.5066933518.

The spelling of 989556647 in words is "nine hundred eighty-nine million, five hundred fifty-six thousand, six hundred forty-seven".