20402064457 has 2 divisors, whose sum is σ = 20402064458. Its totient is φ = 20402064456.

The previous prime is 20402064451. The next prime is 20402064461. The reversal of 20402064457 is 75446020402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18282014521 + 2120049936 = 135211^2 + 46044^2 .

It is a cyclic number.

It is not a de Polignac number, because 20402064457 - 2¹¹ = 20402062409 is a prime.

It is not a weakly prime, because it can be changed into another prime (20402064451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10201032228 + 10201032229.

It is an arithmetic number, because the mean of its divisors is an integer number (10201032229).

Almost surely, 2^20402064457 is an apocalyptic number.

It is an amenable number.

20402064457 is a deficient number, since it is larger than the sum of its proper divisors (1).

20402064457 is an equidigital number, since it uses as much as digits as its factorization.

20402064457 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 53760, while the sum is 34.

Adding to 20402064457 its reverse (75446020402), we get a palindrome (95848084859).

The spelling of 20402064457 in words is "twenty billion, four hundred two million, sixty-four thousand, four hundred fifty-seven".