540070021 has 4 divisors (see below), whose sum is σ = 541068844. Its totient is φ = 539071200.

The previous prime is 540070009. The next prime is 540070051. The reversal of 540070021 is 120070045.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120070045 = 5 ⋅24014009.

It can be written as a sum of positive squares in 2 ways, for example, as 149572900 + 390497121 = 12230^2 + 19761^2 .

It is a cyclic number.

It is not a de Polignac number, because 540070021 - 2⁵ = 540069989 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 (540070051) 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, 498600 + ... + 499681.

It is an arithmetic number, because the mean of its divisors is an integer number (135267211).

Almost surely, 2^540070021 is an apocalyptic number.

It is an amenable number.

540070021 is a deficient number, since it is larger than the sum of its proper divisors (998823).

540070021 is an equidigital number, since it uses as much as digits as its factorization.

540070021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 998822.

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 540070021 is about 23239.4066404459. The cubic root of 540070021 is about 814.3604809083.

The spelling of 540070021 in words is "five hundred forty million, seventy thousand, twenty-one".