101993209 has 2 divisors, whose sum is σ = 101993210. Its totient is φ = 101993208.

The previous prime is 101993207. The next prime is 101993231. The reversal of 101993209 is 902399101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81090025 + 20903184 = 9005^2 + 4572^2 .

It is an emirp because it is prime and its reverse (902399101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 101993209 - 2¹ = 101993207 is a prime.

It is a super-2 number, since 2×101993209² = 20805229364235362, which contains 22 as substring.

Together with 101993207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (101993207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50996604 + 50996605.

It is an arithmetic number, because the mean of its divisors is an integer number (50996605).

Almost surely, 2^101993209 is an apocalyptic number.

It is an amenable number.

101993209 is a deficient number, since it is larger than the sum of its proper divisors (1).

101993209 is an equidigital number, since it uses as much as digits as its factorization.

101993209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4374, while the sum is 34.

The square root of 101993209 is about 10099.1687281677. The cubic root of 101993209 is about 467.2225033948. Note that the first 3 decimals are identical.

The spelling of 101993209 in words is "one hundred one million, nine hundred ninety-three thousand, two hundred nine".