161220356203 has 4 divisors (see below), whose sum is σ = 161247925800. Its totient is φ = 161192786608.

The previous prime is 161220356201. The next prime is 161220356257. The reversal of 161220356203 is 302653022161.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 161220356203 - 2¹ = 161220356201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161220356201) 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, 13776025 + ... + 13787722.

It is an arithmetic number, because the mean of its divisors is an integer number (40311981450).

Almost surely, 2^161220356203 is an apocalyptic number.

161220356203 is a deficient number, since it is larger than the sum of its proper divisors (27569597).

161220356203 is an equidigital number, since it uses as much as digits as its factorization.

161220356203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27569596.

The product of its (nonzero) digits is 12960, while the sum is 31.

Adding to 161220356203 its reverse (302653022161), we get a palindrome (463873378364).

The spelling of 161220356203 in words is "one hundred sixty-one billion, two hundred twenty million, three hundred fifty-six thousand, two hundred three".