42206221 has 4 divisors (see below), whose sum is σ = 43567744. Its totient is φ = 40844700.

The previous prime is 42206209. The next prime is 42206249. The reversal of 42206221 is 12260224.

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 42206221 - 2⁷ = 42206093 is a prime.

It is a super-2 number, since 2×42206221² = 3562730182201682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42206251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 680715 + ... + 680776.

It is an arithmetic number, because the mean of its divisors is an integer number (10891936).

Almost surely, 2^42206221 is an apocalyptic number.

It is an amenable number.

42206221 is a deficient number, since it is larger than the sum of its proper divisors (1361523).

42206221 is a wasteful number, since it uses less digits than its factorization.

42206221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1361522.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 42206221 is about 6496.6315117913. The cubic root of 42206221 is about 348.1706483487.

Adding to 42206221 its reverse (12260224), we get a palindrome (54466445).

The spelling of 42206221 in words is "forty-two million, two hundred six thousand, two hundred twenty-one".