20552433021 has 10 divisors (see below), whose sum is σ = 30701782782. Its totient is φ = 13701621960.

The previous prime is 20552433007. The next prime is 20552433029. The reversal of 20552433021 is 12033425502.

It is a happy number.

20552433021 is a `hidden beast` number, since 20 + 552 + 43 + 30 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 15322973796 + 5229459225 = 123786^2 + 72315^2 .

It is not a de Polignac number, because 20552433021 - 2¹³ = 20552424829 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20552433029) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 126866790 + ... + 126866951.

Almost surely, 2^20552433021 is an apocalyptic number.

It is an amenable number.

20552433021 is a deficient number, since it is larger than the sum of its proper divisors (10149349761).

20552433021 is an equidigital number, since it uses as much as digits as its factorization.

20552433021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253733753 (or 253733744 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 27.

Adding to 20552433021 its reverse (12033425502), we get a palindrome (32585858523).

The spelling of 20552433021 in words is "twenty billion, five hundred fifty-two million, four hundred thirty-three thousand, twenty-one".