50221661 has 4 divisors (see below), whose sum is σ = 57396192. Its totient is φ = 43047132.

The previous prime is 50221609. The next prime is 50221681. The reversal of 50221661 is 16612205.

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: 16612205 = 5 ⋅3322441.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-50221661 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (50221681) 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, 3587255 + ... + 3587268.

It is an arithmetic number, because the mean of its divisors is an integer number (14349048).

Almost surely, 2^50221661 is an apocalyptic number.

It is an amenable number.

50221661 is a deficient number, since it is larger than the sum of its proper divisors (7174531).

50221661 is an equidigital number, since it uses as much as digits as its factorization.

50221661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7174530.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 50221661 is about 7086.7242785366. The cubic root of 50221661 is about 368.9467514226.

Adding to 50221661 its reverse (16612205), we get a palindrome (66833866).

The spelling of 50221661 in words is "fifty million, two hundred twenty-one thousand, six hundred sixty-one".