20418144473 has 2 divisors, whose sum is σ = 20418144474. Its totient is φ = 20418144472.

The previous prime is 20418144469. The next prime is 20418144517. The reversal of 20418144473 is 37444181402.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11520372889 + 8897771584 = 107333^2 + 94328^2 .

It is a cyclic number.

It is not a de Polignac number, because 20418144473 - 2² = 20418144469 is a prime.

It is not a weakly prime, because it can be changed into another prime (20418144403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10209072236 + 10209072237.

It is an arithmetic number, because the mean of its divisors is an integer number (10209072237).

Almost surely, 2^20418144473 is an apocalyptic number.

It is an amenable number.

20418144473 is a deficient number, since it is larger than the sum of its proper divisors (1).

20418144473 is an equidigital number, since it uses as much as digits as its factorization.

20418144473 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 86016, while the sum is 38.

The spelling of 20418144473 in words is "twenty billion, four hundred eighteen million, one hundred forty-four thousand, four hundred seventy-three".