52221661 has 4 divisors (see below), whose sum is σ = 54492192. Its totient is φ = 49951132.

The previous prime is 52221649. The next prime is 52221677. The reversal of 52221661 is 16612225.

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 52221661 - 2⁹ = 52221149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (52221641) 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, 1135231 + ... + 1135276.

It is an arithmetic number, because the mean of its divisors is an integer number (13623048).

Almost surely, 2^52221661 is an apocalyptic number.

It is an amenable number.

52221661 is a deficient number, since it is larger than the sum of its proper divisors (2270531).

52221661 is a wasteful number, since it uses less digits than its factorization.

52221661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2270530.

The product of its digits is 1440, while the sum is 25.

The square root of 52221661 is about 7226.4556319125. The cubic root of 52221661 is about 373.7807178252.

Adding to 52221661 its reverse (16612225), we get a palindrome (68833886).

The spelling of 52221661 in words is "fifty-two million, two hundred twenty-one thousand, six hundred sixty-one".