20381621206459 has 2 divisors, whose sum is σ = 20381621206460. Its totient is φ = 20381621206458.

The previous prime is 20381621206447. The next prime is 20381621206477. The reversal of 20381621206459 is 95460212618302.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20381621206459 - 2³⁹ = 19831865392571 is a prime.

It is not a weakly prime, because it can be changed into another prime (20381621206559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10190810603229 + 10190810603230.

It is an arithmetic number, because the mean of its divisors is an integer number (10190810603230).

Almost surely, 2^{20381621206459} is an apocalyptic number.

20381621206459 is a deficient number, since it is larger than the sum of its proper divisors (1).

20381621206459 is an equidigital number, since it uses as much as digits as its factorization.

20381621206459 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1244160, while the sum is 49.

The spelling of 20381621206459 in words is "twenty trillion, three hundred eighty-one billion, six hundred twenty-one million, two hundred six thousand, four hundred fifty-nine".