42025021 has 4 divisors (see below), whose sum is σ = 42038172. Its totient is φ = 42011872.

The previous prime is 42025001. The next prime is 42025069. The reversal of 42025021 is 12052024.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 37380996 + 4644025 = 6114^2 + 2155^2 .

It is a cyclic number.

It is not a de Polignac number, because 42025021 - 2⁷ = 42024893 is a prime.

It is a super-2 number, since 2×42025021² = 3532204780100882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42024986 and 42025004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42025001) 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, 1641 + ... + 9313.

It is an arithmetic number, because the mean of its divisors is an integer number (10509543).

Almost surely, 2^42025021 is an apocalyptic number.

It is an amenable number.

42025021 is a deficient number, since it is larger than the sum of its proper divisors (13151).

42025021 is an equidigital number, since it uses as much as digits as its factorization.

42025021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13150.

The product of its (nonzero) digits is 160, while the sum is 16.

The square root of 42025021 is about 6482.6708230482. The cubic root of 42025021 is about 347.6716775023.

Adding to 42025021 its reverse (12052024), we get a palindrome (54077045).

It can be divided in two parts, 420 and 25021, that multiplied together give a triangular number (10508820 = T₄₅₈₄).

The spelling of 42025021 in words is "forty-two million, twenty-five thousand, twenty-one".