201676561 has 4 divisors (see below), whose sum is σ = 202565232. Its totient is φ = 200787892.

The previous prime is 201676549. The next prime is 201676567. The reversal of 201676561 is 165676102.

It is a happy number.

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: 165676102 = 2 ⋅82838051.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201676561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201676567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 443995 + ... + 444448.

It is an arithmetic number, because the mean of its divisors is an integer number (50641308).

Almost surely, 2^201676561 is an apocalyptic number.

It is an amenable number.

201676561 is a deficient number, since it is larger than the sum of its proper divisors (888671).

201676561 is an equidigital number, since it uses as much as digits as its factorization.

201676561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 888670.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 201676561 is about 14201.2873008048. The cubic root of 201676561 is about 586.4331007154.

The spelling of 201676561 in words is "two hundred one million, six hundred seventy-six thousand, five hundred sixty-one".