161613601 has 4 divisors (see below), whose sum is σ = 170119600. Its totient is φ = 153107604.

The previous prime is 161613593. The next prime is 161613619. The reversal of 161613601 is 106316161.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 161613601 - 2³ = 161613593 is a prime.

It is a super-2 number, since 2×161613601² = 52237912056374402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161613691) 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, 4252971 + ... + 4253008.

It is an arithmetic number, because the mean of its divisors is an integer number (42529900).

Almost surely, 2^161613601 is an apocalyptic number.

It is an amenable number.

161613601 is a deficient number, since it is larger than the sum of its proper divisors (8505999).

161613601 is an equidigital number, since it uses as much as digits as its factorization.

161613601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8505998.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 161613601 is about 12712.7338129924. The cubic root of 161613601 is about 544.7024170108.

Adding to 161613601 its reverse (106316161), we get a palindrome (267929762).

The spelling of 161613601 in words is "one hundred sixty-one million, six hundred thirteen thousand, six hundred one".