989897391 has 24 divisors (see below), whose sum is σ = 1705167360. Its totient is φ = 541061136.

The previous prime is 989897353. The next prime is 989897393. The reversal of 989897391 is 193798989.

It is not a de Polignac number, because 989897391 - 2⁶ = 989897327 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (989897393) 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, 340131 + ... + 343028.

It is an arithmetic number, because the mean of its divisors is an integer number (71048640).

Almost surely, 2^989897391 is an apocalyptic number.

989897391 is a deficient number, since it is larger than the sum of its proper divisors (715269969).

989897391 is a wasteful number, since it uses less digits than its factorization.

989897391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 683195 (or 683192 counting only the distinct ones).

The product of its digits is 8817984, while the sum is 63.

The square root of 989897391 is about 31462.6348388052. The cubic root of 989897391 is about 996.6210592857.

The spelling of 989897391 in words is "nine hundred eighty-nine million, eight hundred ninety-seven thousand, three hundred ninety-one".