999636997 has 2 divisors, whose sum is σ = 999636998.
Its totient is φ = 999636996.
The previous prime is 999636991. The next prime is 999637003. The reversal of 999636997 is 799636999.
It is a balanced prime because it is at equal distance from previous prime (999636991) and next prime (999637003).
It can be written as a sum of positive squares in only one way, i.e., 736905316 + 262731681 = 27146^2 + 16209^2
999636997 is a truncatable prime.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-999636997 is a prime.
It is a Chen prime.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (999636991) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499818498 + 499818499.
It is an arithmetic number, because the mean of its divisors is an integer number (499818499).
Almost surely, 2999636997 is an apocalyptic number.
It is an amenable number.
999636997 is a deficient number, since it is larger than the sum of its proper divisors (1).
999636997 is an equidigital number, since it uses as much as digits as its factorization.
999636997 is an evil number, because the sum of its binary digits is even.
The product of its digits is 44641044, while the sum is 67.
The square root of 999636997 is about 31617.0364993305.
The cubic root of 999636997 is about 999.8789843558.
The spelling of 999636997 in words is "nine hundred ninety-nine million, six hundred thirty-six thousand, nine hundred ninety-seven".