897389991 has 12 divisors (see below), whose sum is σ = 1297300680. Its totient is φ = 597765840.

The previous prime is 897389959. The next prime is 897390017. The reversal of 897389991 is 199983798.

It is not a de Polignac number, because 897389991 - 2⁵ = 897389959 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (897389921) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29505 + ... + 51626.

It is an arithmetic number, because the mean of its divisors is an integer number (108108390).

Almost surely, 2^897389991 is an apocalyptic number.

897389991 is a deficient number, since it is larger than the sum of its proper divisors (399910689).

897389991 is a wasteful number, since it uses less digits than its factorization.

897389991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82366 (or 82363 counting only the distinct ones).

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

The square root of 897389991 is about 29956.4682664696. The cubic root of 897389991 is about 964.5551713234. Note that the first 3 decimals are identical.

The spelling of 897389991 in words is "eight hundred ninety-seven million, three hundred eighty-nine thousand, nine hundred ninety-one".