20436056491 has 2 divisors, whose sum is σ = 20436056492. Its totient is φ = 20436056490.

The previous prime is 20436056489. The next prime is 20436056519. The reversal of 20436056491 is 19465063402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20436056491 - 2¹ = 20436056489 is a prime.

Together with 20436056489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20436056591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10218028245 + 10218028246.

It is an arithmetic number, because the mean of its divisors is an integer number (10218028246).

Almost surely, 2^20436056491 is an apocalyptic number.

20436056491 is a deficient number, since it is larger than the sum of its proper divisors (1).

20436056491 is an equidigital number, since it uses as much as digits as its factorization.

20436056491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 155520, while the sum is 40.

The spelling of 20436056491 in words is "twenty billion, four hundred thirty-six million, fifty-six thousand, four hundred ninety-one".