20000643601 has 2 divisors, whose sum is σ = 20000643602. Its totient is φ = 20000643600.

The previous prime is 20000643511. The next prime is 20000643629. The reversal of 20000643601 is 10634600002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19565295376 + 435348225 = 139876^2 + 20865^2 .

It is a cyclic number.

It is not a de Polignac number, because 20000643601 - 2¹⁹ = 20000119313 is a prime.

It is not a weakly prime, because it can be changed into another prime (20000643671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000321800 + 10000321801.

It is an arithmetic number, because the mean of its divisors is an integer number (10000321801).

Almost surely, 2^20000643601 is an apocalyptic number.

It is an amenable number.

20000643601 is a deficient number, since it is larger than the sum of its proper divisors (1).

20000643601 is an equidigital number, since it uses as much as digits as its factorization.

20000643601 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 22.

The spelling of 20000643601 in words is "twenty billion, six hundred forty-three thousand, six hundred one".