9921986 has 8 divisors (see below), whose sum is σ = 15062544. Its totient is φ = 4901140.

The previous prime is 9921983. The next prime is 9921991. The reversal of 9921986 is 6891299.

9921986 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×9921986³ (a number of 22 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (9921983) 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, 29720 + ... + 30051.

It is an arithmetic number, because the mean of its divisors is an integer number (1882818).

Almost surely, 2^9921986 is an apocalyptic number.

9921986 is a deficient number, since it is larger than the sum of its proper divisors (5140558).

9921986 is a wasteful number, since it uses less digits than its factorization.

9921986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59856.

The product of its digits is 69984, while the sum is 44.

The square root of 9921986 is about 3149.9184116418. The cubic root of 9921986 is about 214.8817521753.

The spelling of 9921986 in words is "nine million, nine hundred twenty-one thousand, nine hundred eighty-six".