20535542021 has 8 divisors (see below), whose sum is σ = 20925343224. Its totient is φ = 20145827520.

The previous prime is 20535541997. The next prime is 20535542033. The reversal of 20535542021 is 12024553502.

It can be written as a sum of positive squares in 4 ways, for example, as 7142109121 + 13393432900 = 84511^2 + 115730^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20535542021 - 2¹⁰ = 20535540997 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 (20535542051) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 654431 + ... + 685091.

It is an arithmetic number, because the mean of its divisors is an integer number (2615667903).

Almost surely, 2^20535542021 is an apocalyptic number.

It is an amenable number.

20535542021 is a deficient number, since it is larger than the sum of its proper divisors (389801203).

20535542021 is a wasteful number, since it uses less digits than its factorization.

20535542021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43351.

The product of its (nonzero) digits is 12000, while the sum is 29.

The spelling of 20535542021 in words is "twenty billion, five hundred thirty-five million, five hundred forty-two thousand, twenty-one".