161724791 has 8 divisors (see below), whose sum is σ = 174882240. Its totient is φ = 148972288.

The previous prime is 161724781. The next prime is 161724821. The reversal of 161724791 is 197427161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161724791 - 2¹⁰ = 161723767 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161724781) 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 in 7 ways as a sum of consecutive naturals, for example, 100406 + ... + 102003.

It is an arithmetic number, because the mean of its divisors is an integer number (21860280).

Almost surely, 2^161724791 is an apocalyptic number.

161724791 is a deficient number, since it is larger than the sum of its proper divisors (13157449).

161724791 is a wasteful number, since it uses less digits than its factorization.

161724791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202473.

The product of its digits is 21168, while the sum is 38.

The square root of 161724791 is about 12717.1062353037. The cubic root of 161724791 is about 544.8273066179.

The spelling of 161724791 in words is "one hundred sixty-one million, seven hundred twenty-four thousand, seven hundred ninety-one".