9981906 has 16 divisors (see below), whose sum is σ = 21778848. Its totient is φ = 3024800.

The previous prime is 9981899. The next prime is 9981911. The reversal of 9981906 is 6091899.

9981906 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75555 + ... + 75686.

It is an arithmetic number, because the mean of its divisors is an integer number (1361178).

Almost surely, 2^9981906 is an apocalyptic number.

9981906 is an abundant number, since it is smaller than the sum of its proper divisors (11796942).

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

9981906 is a wasteful number, since it uses less digits than its factorization.

9981906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151257.

The product of its (nonzero) digits is 34992, while the sum is 42.

The square root of 9981906 is about 3159.4154522633. The cubic root of 9981906 is about 215.3134494149.

The spelling of 9981906 in words is "nine million, nine hundred eighty-one thousand, nine hundred six".