999997679 has 2 divisors, whose sum is σ = 999997680. Its totient is φ = 999997678.

The previous prime is 999997673. The next prime is 999997697. The reversal of 999997679 is 976799999.

Together with next prime (999997697) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 999997679 - 2¹² = 999993583 is a prime.

It is a super-3 number, since 3×999997679³ (a number of 28 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999997673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499998839 + 499998840.

It is an arithmetic number, because the mean of its divisors is an integer number (499998840).

Almost surely, 2^999997679 is an apocalyptic number.

999997679 is a deficient number, since it is larger than the sum of its proper divisors (1).

999997679 is an equidigital number, since it uses as much as digits as its factorization.

999997679 is an evil number, because the sum of its binary digits is even.

The product of its digits is 156243654, while the sum is 74.

The square root of 999997679 is about 31622.7399034303. The cubic root of 999997679 is about 999.9992263327. Note that the first 3 decimals are identical.

The spelling of 999997679 in words is "nine hundred ninety-nine million, nine hundred ninety-seven thousand, six hundred seventy-nine".