999998997 has 8 divisors (see below), whose sum is σ = 1333522560. Its totient is φ = 666570720.

The previous prime is 999998981. The next prime is 999999001. The reversal of 999998997 is 799899999.

It is a happy number.

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

It is not a de Polignac number, because 999998997 - 2⁴ = 999998981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999998917) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6004 + ... + 45122.

It is an arithmetic number, because the mean of its divisors is an integer number (166690320).

Almost surely, 2^999998997 is an apocalyptic number.

It is an amenable number.

999998997 is a deficient number, since it is larger than the sum of its proper divisors (333523563).

999998997 is a wasteful number, since it uses less digits than its factorization.

999998997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47643.

The product of its digits is 267846264, while the sum is 78.

The square root of 999998997 is about 31622.7607428574. The cubic root of 999998997 is about 999.9996656666. Note that the first 3 decimals are identical.

The spelling of 999998997 in words is "nine hundred ninety-nine million, nine hundred ninety-eight thousand, nine hundred ninety-seven".