128997816 has 16 divisors (see below), whose sum is σ = 322494600. Its totient is φ = 42999264.

The previous prime is 128997811. The next prime is 128997833. The reversal of 128997816 is 618799821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128997811) 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, 2687431 + ... + 2687478.

Almost surely, 2^128997816 is an apocalyptic number.

It is an amenable number.

128997816 is an abundant number, since it is smaller than the sum of its proper divisors (193496784).

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

128997816 is a wasteful number, since it uses less digits than its factorization.

128997816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5374918 (or 5374914 counting only the distinct ones).

The product of its digits is 435456, while the sum is 51.

The square root of 128997816 is about 11357.7205459546. The cubic root of 128997816 is about 505.2745832166.

The spelling of 128997816 in words is "one hundred twenty-eight million, nine hundred ninety-seven thousand, eight hundred sixteen".