20645108401 has 2 divisors, whose sum is σ = 20645108402. Its totient is φ = 20645108400.

The previous prime is 20645108387. The next prime is 20645108413. The reversal of 20645108401 is 10480154602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10867854001 + 9777254400 = 104249^2 + 98880^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20645108401 is a prime.

It is not a weakly prime, because it can be changed into another prime (20645108101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10322554200 + 10322554201.

It is an arithmetic number, because the mean of its divisors is an integer number (10322554201).

Almost surely, 2^20645108401 is an apocalyptic number.

It is an amenable number.

20645108401 is a deficient number, since it is larger than the sum of its proper divisors (1).

20645108401 is an equidigital number, since it uses as much as digits as its factorization.

20645108401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7680, while the sum is 31.

The spelling of 20645108401 in words is "twenty billion, six hundred forty-five million, one hundred eight thousand, four hundred one".