161517793 has 8 divisors (see below), whose sum is σ = 163239336. Its totient is φ = 159801600.

The previous prime is 161517787. The next prime is 161517821. The reversal of 161517793 is 397715161.

It can be written as a sum of positive squares in 4 ways, for example, as 27699169 + 133818624 = 5263^2 + 11568^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161517793 is a prime.

It is a super-4 number, since 4×161517793⁴ (a number of 34 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161517193) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91903 + ... + 93643.

It is an arithmetic number, because the mean of its divisors is an integer number (20404917).

Almost surely, 2^161517793 is an apocalyptic number.

It is an amenable number.

161517793 is a deficient number, since it is larger than the sum of its proper divisors (1721543).

161517793 is a wasteful number, since it uses less digits than its factorization.

161517793 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2675.

The product of its digits is 39690, while the sum is 40.

The square root of 161517793 is about 12708.9650640798. The cubic root of 161517793 is about 544.5947586521.

The spelling of 161517793 in words is "one hundred sixty-one million, five hundred seventeen thousand, seven hundred ninety-three".