209210181923 has 2 divisors, whose sum is σ = 209210181924. Its totient is φ = 209210181922.

The previous prime is 209210181911. The next prime is 209210181959. The reversal of 209210181923 is 329181012902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 209210181923 - 2¹⁶ = 209210116387 is a prime.

It is not a weakly prime, because it can be changed into another prime (209210181023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104605090961 + 104605090962.

It is an arithmetic number, because the mean of its divisors is an integer number (104605090962).

Almost surely, 2^209210181923 is an apocalyptic number.

209210181923 is a deficient number, since it is larger than the sum of its proper divisors (1).

209210181923 is an equidigital number, since it uses as much as digits as its factorization.

209210181923 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 38.

The spelling of 209210181923 in words is "two hundred nine billion, two hundred ten million, one hundred eighty-one thousand, nine hundred twenty-three".