9991995 has 16 divisors (see below), whose sum is σ = 17217312. Its totient is φ = 4919040.

The previous prime is 9991973. The next prime is 9991997. The reversal of 9991995 is 5991999.

It is not a de Polignac number, because 9991995 - 2⁵ = 9991963 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9991997) 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, 25426 + ... + 25815.

It is an arithmetic number, because the mean of its divisors is an integer number (1076082).

Almost surely, 2^9991995 is an apocalyptic number.

9991995 is a deficient number, since it is larger than the sum of its proper divisors (7225317).

9991995 is a wasteful number, since it uses less digits than its factorization.

9991995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51262.

The product of its digits is 295245, while the sum is 51.

The square root of 9991995 is about 3161.0117051349. The cubic root of 9991995 is about 215.3859661578.

The spelling of 9991995 in words is "nine million, nine hundred ninety-one thousand, nine hundred ninety-five".