20621504533 has 4 divisors (see below), whose sum is σ = 23567433760. Its totient is φ = 17675575308.

The previous prime is 20621504531. The next prime is 20621504587. The reversal of 20621504533 is 33540512602.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20621504533 - 2¹ = 20621504531 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20621504495 and 20621504504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20621504531) 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, 1472964603 + ... + 1472964616.

It is an arithmetic number, because the mean of its divisors is an integer number (5891858440).

Almost surely, 2^20621504533 is an apocalyptic number.

It is an amenable number.

20621504533 is a deficient number, since it is larger than the sum of its proper divisors (2945929227).

20621504533 is an equidigital number, since it uses as much as digits as its factorization.

20621504533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2945929226.

The product of its (nonzero) digits is 21600, while the sum is 31.

The spelling of 20621504533 in words is "twenty billion, six hundred twenty-one million, five hundred four thousand, five hundred thirty-three".