20635221433 has 4 divisors (see below), whose sum is σ = 20636216308. Its totient is φ = 20634226560.

The previous prime is 20635221421. The next prime is 20635221457. The reversal of 20635221433 is 33412253602.

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 6308807184 + 14326414249 = 79428^2 + 119693^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20635221433 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20635221395 and 20635221404.

It is not an unprimeable number, because it can be changed into a prime (20635231433) 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, 465648 + ... + 508033.

It is an arithmetic number, because the mean of its divisors is an integer number (5159054077).

Almost surely, 2^20635221433 is an apocalyptic number.

It is an amenable number.

20635221433 is a deficient number, since it is larger than the sum of its proper divisors (994875).

20635221433 is an equidigital number, since it uses as much as digits as its factorization.

20635221433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 994874.

The product of its (nonzero) digits is 25920, while the sum is 31.

The spelling of 20635221433 in words is "twenty billion, six hundred thirty-five million, two hundred twenty-one thousand, four hundred thirty-three".