42559021 has 2 divisors, whose sum is σ = 42559022. Its totient is φ = 42559020.

The previous prime is 42558983. The next prime is 42559043. The reversal of 42559021 is 12095524.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 37088100 + 5470921 = 6090^2 + 2339^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42559021 is a prime.

It is a super-2 number, since 2×42559021² = 3622540536956882, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42551021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21279510 + 21279511.

It is an arithmetic number, because the mean of its divisors is an integer number (21279511).

Almost surely, 2^42559021 is an apocalyptic number.

It is an amenable number.

42559021 is a deficient number, since it is larger than the sum of its proper divisors (1).

42559021 is an equidigital number, since it uses as much as digits as its factorization.

42559021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3600, while the sum is 28.

The square root of 42559021 is about 6523.7275387619. The cubic root of 42559021 is about 349.1380723130.

It can be divided in two parts, 4255902 and 1, that added together give a triangular number (4255903 = T₂₉₁₇).

The spelling of 42559021 in words is "forty-two million, five hundred fifty-nine thousand, twenty-one".