161813713 has 4 divisors (see below), whose sum is σ = 162027108. Its totient is φ = 161600320.

The previous prime is 161813711. The next prime is 161813723. The reversal of 161813713 is 317318161.

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

It can be written as a sum of positive squares in 2 ways, for example, as 41319184 + 120494529 = 6428^2 + 10977^2 .

It is a cyclic number.

It is not a de Polignac number, because 161813713 - 2¹ = 161813711 is a prime.

It is a super-3 number, since 3×161813713³ (a number of 26 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161813711) 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, 105556 + ... + 107077.

It is an arithmetic number, because the mean of its divisors is an integer number (40506777).

Almost surely, 2^161813713 is an apocalyptic number.

It is an amenable number.

161813713 is a deficient number, since it is larger than the sum of its proper divisors (213395).

161813713 is an equidigital number, since it uses as much as digits as its factorization.

161813713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213394.

The product of its digits is 3024, while the sum is 31.

The square root of 161813713 is about 12720.6019118594. The cubic root of 161813713 is about 544.9271434185.

The spelling of 161813713 in words is "one hundred sixty-one million, eight hundred thirteen thousand, seven hundred thirteen".