20384736257 has 2 divisors, whose sum is σ = 20384736258. Its totient is φ = 20384736256.

The previous prime is 20384736233. The next prime is 20384736277. The reversal of 20384736257 is 75263748302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14476661761 + 5908074496 = 120319^2 + 76864^2 .

It is a cyclic number.

It is not a de Polignac number, because 20384736257 - 2¹² = 20384732161 is a prime.

It is not a weakly prime, because it can be changed into another prime (20384736277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10192368128 + 10192368129.

It is an arithmetic number, because the mean of its divisors is an integer number (10192368129).

Almost surely, 2^20384736257 is an apocalyptic number.

It is an amenable number.

20384736257 is a deficient number, since it is larger than the sum of its proper divisors (1).

20384736257 is an equidigital number, since it uses as much as digits as its factorization.

20384736257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1693440, while the sum is 47.

The spelling of 20384736257 in words is "twenty billion, three hundred eighty-four million, seven hundred thirty-six thousand, two hundred fifty-seven".