20440334643 has 4 divisors (see below), whose sum is σ = 27253779528. Its totient is φ = 13626889760.

The previous prime is 20440334597. The next prime is 20440334657. The reversal of 20440334643 is 34643304402.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20440334643 - 2¹⁷ = 20440203571 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20440334143) 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, 3406722438 + ... + 3406722443.

It is an arithmetic number, because the mean of its divisors is an integer number (6813444882).

Almost surely, 2^20440334643 is an apocalyptic number.

20440334643 is a deficient number, since it is larger than the sum of its proper divisors (6813444885).

20440334643 is an equidigital number, since it uses as much as digits as its factorization.

20440334643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6813444884.

The product of its (nonzero) digits is 82944, while the sum is 33.

The spelling of 20440334643 in words is "twenty billion, four hundred forty million, three hundred thirty-four thousand, six hundred forty-three".