99138709 has 2 divisors, whose sum is σ = 99138710. Its totient is φ = 99138708.

The previous prime is 99138707. The next prime is 99138731. The reversal of 99138709 is 90783199.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 97950609 + 1188100 = 9897^2 + 1090^2 .

It is a cyclic number.

It is not a de Polignac number, because 99138709 - 2¹ = 99138707 is a prime.

It is a super-4 number, since 4×99138709⁴ (a number of 33 digits) contains 4444 as substring.

Together with 99138707, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99138707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49569354 + 49569355.

It is an arithmetic number, because the mean of its divisors is an integer number (49569355).

Almost surely, 2^99138709 is an apocalyptic number.

It is an amenable number.

99138709 is a deficient number, since it is larger than the sum of its proper divisors (1).

99138709 is an equidigital number, since it uses as much as digits as its factorization.

99138709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 122472, while the sum is 46.

The square root of 99138709 is about 9956.8423207360. The cubic root of 99138709 is about 462.8224529047.

The spelling of 99138709 in words is "ninety-nine million, one hundred thirty-eight thousand, seven hundred nine".