161210661638339 has 4 divisors (see below), whose sum is σ = 161227697541456. Its totient is φ = 161193625735224.

The previous prime is 161210661638321. The next prime is 161210661638393. The reversal of 161210661638339 is 933836166012161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161210661638339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161210661638539) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8517937364 + ... + 8517956289.

It is an arithmetic number, because the mean of its divisors is an integer number (40306924385364).

Almost surely, 2^{161210661638339} is an apocalyptic number.

161210661638339 is a deficient number, since it is larger than the sum of its proper divisors (17035903117).

161210661638339 is an equidigital number, since it uses as much as digits as its factorization.

161210661638339 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17035903116.

The product of its (nonzero) digits is 5038848, while the sum is 56.

The spelling of 161210661638339 in words is "one hundred sixty-one trillion, two hundred ten billion, six hundred sixty-one million, six hundred thirty-eight thousand, three hundred thirty-nine".