601221561 has 4 divisors (see below), whose sum is σ = 801628752. Its totient is φ = 400814372.

The previous prime is 601221497. The next prime is 601221563. The reversal of 601221561 is 165122106.

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 601221561 - 2⁶ = 601221497 is a prime.

It is a super-2 number, since 2×601221561² = 722934730822553442, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (601221563) 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, 100203591 + ... + 100203596.

It is an arithmetic number, because the mean of its divisors is an integer number (200407188).

Almost surely, 2^601221561 is an apocalyptic number.

It is an amenable number.

601221561 is a deficient number, since it is larger than the sum of its proper divisors (200407191).

601221561 is a wasteful number, since it uses less digits than its factorization.

601221561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200407190.

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 601221561 is about 24519.8197587176. The cubic root of 601221561 is about 844.0046686511.

Adding to 601221561 its reverse (165122106), we get a palindrome (766343667).

The spelling of 601221561 in words is "six hundred one million, two hundred twenty-one thousand, five hundred sixty-one".