20356641043 has 4 divisors (see below), whose sum is σ = 20357120680. Its totient is φ = 20356161408.

The previous prime is 20356641029. The next prime is 20356641101. The reversal of 20356641043 is 34014665302.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34014665302 = 2 ⋅17007332651.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20356641043 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20356648043) 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, 169230 + ... + 263347.

It is an arithmetic number, because the mean of its divisors is an integer number (5089280170).

Almost surely, 2^20356641043 is an apocalyptic number.

20356641043 is a deficient number, since it is larger than the sum of its proper divisors (479637).

20356641043 is an equidigital number, since it uses as much as digits as its factorization.

20356641043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 479636.

The product of its (nonzero) digits is 51840, while the sum is 34.

The spelling of 20356641043 in words is "twenty billion, three hundred fifty-six million, six hundred forty-one thousand, forty-three".