20195433581 has 4 divisors (see below), whose sum is σ = 20202451200. Its totient is φ = 20188415964.

The previous prime is 20195433553. The next prime is 20195433649. The reversal of 20195433581 is 18533459102.

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, and also an emirpimes, since its reverse is a distinct semiprime: 18533459102 = 2 ⋅9266729551.

It is a cyclic number.

It is not a de Polignac number, because 20195433581 - 2¹⁴ = 20195417197 is a prime.

It is a super-2 number, since 2×20195433581² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20195433551) 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, 3504491 + ... + 3510248.

It is an arithmetic number, because the mean of its divisors is an integer number (5050612800).

Almost surely, 2^20195433581 is an apocalyptic number.

It is an amenable number.

20195433581 is a deficient number, since it is larger than the sum of its proper divisors (7017619).

20195433581 is an equidigital number, since it uses as much as digits as its factorization.

20195433581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7017618.

The product of its (nonzero) digits is 129600, while the sum is 41.

The spelling of 20195433581 in words is "twenty billion, one hundred ninety-five million, four hundred thirty-three thousand, five hundred eighty-one".