42672221 has 2 divisors, whose sum is σ = 42672222. Its totient is φ = 42672220.

The previous prime is 42672187. The next prime is 42672241. The reversal of 42672221 is 12227624.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39866596 + 2805625 = 6314^2 + 1675^2 .

It is a cyclic number.

It is not a de Polignac number, because 42672221 - 2²² = 38477917 is a prime.

It is a super-3 number, since 3×42672221³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42672241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21336110 + 21336111.

It is an arithmetic number, because the mean of its divisors is an integer number (21336111).

Almost surely, 2^42672221 is an apocalyptic number.

It is an amenable number.

42672221 is a deficient number, since it is larger than the sum of its proper divisors (1).

42672221 is an equidigital number, since it uses as much as digits as its factorization.

42672221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2688, while the sum is 26.

The square root of 42672221 is about 6532.3977986647. The cubic root of 42672221 is about 349.4473482275.

Adding to 42672221 its reverse (12227624), we get a palindrome (54899845).

It can be divided in two parts, 42 and 672221, that multiplied together give a palindrome (28233282).

The spelling of 42672221 in words is "forty-two million, six hundred seventy-two thousand, two hundred twenty-one".