21600161939 has 2 divisors, whose sum is σ = 21600161940. Its totient is φ = 21600161938.

The previous prime is 21600161887. The next prime is 21600161941. The reversal of 21600161939 is 93916100612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21600161939 - 2⁸ = 21600161683 is a prime.

Together with 21600161941, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21600161969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10800080969 + 10800080970.

It is an arithmetic number, because the mean of its divisors is an integer number (10800080970).

Almost surely, 2^21600161939 is an apocalyptic number.

21600161939 is a deficient number, since it is larger than the sum of its proper divisors (1).

21600161939 is an equidigital number, since it uses as much as digits as its factorization.

21600161939 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17496, while the sum is 38.

The spelling of 21600161939 in words is "twenty-one billion, six hundred million, one hundred sixty-one thousand, nine hundred thirty-nine".