42054021 has 6 divisors (see below), whose sum is σ = 60744710. Its totient is φ = 28036008.

The previous prime is 42054017. The next prime is 42054029. The reversal of 42054021 is 12045024.

It can be written as a sum of positive squares in only one way, i.e., 27720225 + 14333796 = 5265^2 + 3786^2 .

It is not a de Polignac number, because 42054021 - 2² = 42054017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 42053985 and 42054003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42054029) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2336326 + ... + 2336343.

Almost surely, 2^42054021 is an apocalyptic number.

It is an amenable number.

42054021 is a deficient number, since it is larger than the sum of its proper divisors (18690689).

42054021 is a wasteful number, since it uses less digits than its factorization.

42054021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4672675 (or 4672672 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 42054021 is about 6484.9071697288. The cubic root of 42054021 is about 347.7516311435.

Adding to 42054021 its reverse (12045024), we get a palindrome (54099045).

The spelling of 42054021 in words is "forty-two million, fifty-four thousand, twenty-one".