161501601 has 8 divisors (see below), whose sum is σ = 215686944. Its totient is φ = 107492000.

The previous prime is 161501579. The next prime is 161501629. The reversal of 161501601 is 106105161.

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-161501601 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (161501651) 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, 41775 + ... + 45476.

It is an arithmetic number, because the mean of its divisors is an integer number (26960868).

Almost surely, 2^161501601 is an apocalyptic number.

It is an amenable number.

161501601 is a deficient number, since it is larger than the sum of its proper divisors (54185343).

161501601 is an equidigital number, since it uses as much as digits as its factorization.

161501601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87871.

The product of its (nonzero) digits is 180, while the sum is 21.

The square root of 161501601 is about 12708.3280174852. The cubic root of 161501601 is about 544.5765596809.

Adding to 161501601 its reverse (106105161), we get a palindrome (267606762).

The spelling of 161501601 in words is "one hundred sixty-one million, five hundred one thousand, six hundred one".