542036021 has 4 divisors (see below), whose sum is σ = 542110092. Its totient is φ = 541961952.

The previous prime is 542036017. The next prime is 542036039. The reversal of 542036021 is 120630245.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 85359121 + 456676900 = 9239^2 + 21370^2 .

It is a cyclic number.

It is not a de Polignac number, because 542036021 - 2² = 542036017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (542036221) 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, 24686 + ... + 41151.

It is an arithmetic number, because the mean of its divisors is an integer number (135527523).

Almost surely, 2^542036021 is an apocalyptic number.

It is an amenable number.

542036021 is a deficient number, since it is larger than the sum of its proper divisors (74071).

542036021 is an equidigital number, since it uses as much as digits as its factorization.

542036021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74070.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 542036021 is about 23281.6670580094. The cubic root of 542036021 is about 815.3474479268.

Adding to 542036021 its reverse (120630245), we get a palindrome (662666266).

The spelling of 542036021 in words is "five hundred forty-two million, thirty-six thousand, twenty-one".