20440639065601 has 2 divisors, whose sum is σ = 20440639065602. Its totient is φ = 20440639065600.

The previous prime is 20440639065589. The next prime is 20440639065677. The reversal of 20440639065601 is 10656093604402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15955223371201 + 4485415694400 = 3994399^2 + 2117880^2 .

It is a cyclic number.

It is not a de Polignac number, because 20440639065601 - 2³⁵ = 20406279327233 is a prime.

It is not a weakly prime, because it can be changed into another prime (20440639465601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10220319532800 + 10220319532801.

It is an arithmetic number, because the mean of its divisors is an integer number (10220319532801).

Almost surely, 2^{20440639065601} is an apocalyptic number.

It is an amenable number.

20440639065601 is a deficient number, since it is larger than the sum of its proper divisors (1).

20440639065601 is an equidigital number, since it uses as much as digits as its factorization.

20440639065601 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 933120, while the sum is 46.

The spelling of 20440639065601 in words is "twenty trillion, four hundred forty billion, six hundred thirty-nine million, sixty-five thousand, six hundred one".