36221561 has 4 divisors (see below), whose sum is σ = 36295824. Its totient is φ = 36147300.

The previous prime is 36221519. The next prime is 36221569. The reversal of 36221561 is 16512263.

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 36221561 - 2¹⁰ = 36220537 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 36221561.

It is not an unprimeable number, because it can be changed into a prime (36221569) 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, 36395 + ... + 37376.

It is an arithmetic number, because the mean of its divisors is an integer number (9073956).

Almost surely, 2^36221561 is an apocalyptic number.

It is an amenable number.

36221561 is a deficient number, since it is larger than the sum of its proper divisors (74263).

36221561 is an equidigital number, since it uses as much as digits as its factorization.

36221561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74262.

The product of its digits is 2160, while the sum is 26.

The square root of 36221561 is about 6018.4350956042. The cubic root of 36221561 is about 330.8687272855.

The spelling of 36221561 in words is "thirty-six million, two hundred twenty-one thousand, five hundred sixty-one".