56221221 has 8 divisors (see below), whose sum is σ = 85670464. Its totient is φ = 32126400.

The previous prime is 56221213. The next prime is 56221273. The reversal of 56221221 is 12212265.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 56221221 - 2³ = 56221213 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 2677201 = 56221221 / (5 + 6 + 2 + 2 + 1 + 2 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56221201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1338580 + ... + 1338621.

It is an arithmetic number, because the mean of its divisors is an integer number (10708808).

Almost surely, 2^56221221 is an apocalyptic number.

It is an amenable number.

56221221 is a deficient number, since it is larger than the sum of its proper divisors (29449243).

56221221 is a wasteful number, since it uses less digits than its factorization.

56221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2677211.

The product of its digits is 480, while the sum is 21.

The square root of 56221221 is about 7498.0811545355. The cubic root of 56221221 is about 383.0893609929.

Adding to 56221221 its reverse (12212265), we get a palindrome (68433486).

It can be divided in two parts, 5 and 6221221, that added together give a palindrome (6221226).

The spelling of 56221221 in words is "fifty-six million, two hundred twenty-one thousand, two hundred twenty-one".