201561017 has 4 divisors (see below), whose sum is σ = 230355456. Its totient is φ = 172766580.

The previous prime is 201561011. The next prime is 201561037. The reversal of 201561017 is 710165102.

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, and also an emirpimes, since its reverse is a distinct semiprime: 710165102 = 2 ⋅355082551.

It is not a de Polignac number, because 201561017 - 2⁸ = 201560761 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201560983 and 201561001.

It is not an unprimeable number, because it can be changed into a prime (201561011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14397209 + ... + 14397222.

It is an arithmetic number, because the mean of its divisors is an integer number (57588864).

Almost surely, 2^201561017 is an apocalyptic number.

It is an amenable number.

201561017 is a deficient number, since it is larger than the sum of its proper divisors (28794439).

201561017 is an equidigital number, since it uses as much as digits as its factorization.

201561017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28794438.

The product of its (nonzero) digits is 420, while the sum is 23.

The square root of 201561017 is about 14197.2186360569. The cubic root of 201561017 is about 586.3210867559.

The spelling of 201561017 in words is "two hundred one million, five hundred sixty-one thousand, seventeen".