9998781 has 16 divisors (see below), whose sum is σ = 14414400. Its totient is φ = 6128640.

The previous prime is 9998777. The next prime is 9998797. The reversal of 9998781 is 1878999.

9998781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9998781 - 2² = 9998777 is a prime.

It is a super-2 number, since 2×9998781² = 199951242971922, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9998701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17226 + ... + 17796.

It is an arithmetic number, because the mean of its divisors is an integer number (900900).

Almost surely, 2^9998781 is an apocalyptic number.

It is an amenable number.

9998781 is a deficient number, since it is larger than the sum of its proper divisors (4415619).

9998781 is a wasteful number, since it uses less digits than its factorization.

9998781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1036.

The product of its digits is 326592, while the sum is 51.

The square root of 9998781 is about 3162.0849134709. The cubic root of 9998781 is about 215.4347144612.

The spelling of 9998781 in words is "nine million, nine hundred ninety-eight thousand, seven hundred eighty-one".