20965364057257 has 2 divisors, whose sum is σ = 20965364057258. Its totient is φ = 20965364057256.

The previous prime is 20965364057243. The next prime is 20965364057303. The reversal of 20965364057257 is 75275046356902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19007760124521 + 1957603932736 = 4359789^2 + 1399144^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20965364057257 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20965364057195 and 20965364057204.

It is not a weakly prime, because it can be changed into another prime (20965364057557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10482682028628 + 10482682028629.

It is an arithmetic number, because the mean of its divisors is an integer number (10482682028629).

Almost surely, 2^{20965364057257} is an apocalyptic number.

It is an amenable number.

20965364057257 is a deficient number, since it is larger than the sum of its proper divisors (1).

20965364057257 is an equidigital number, since it uses as much as digits as its factorization.

20965364057257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 95256000, while the sum is 61.

The spelling of 20965364057257 in words is "twenty trillion, nine hundred sixty-five billion, three hundred sixty-four million, fifty-seven thousand, two hundred fifty-seven".