21404202947 has 2 divisors, whose sum is σ = 21404202948. Its totient is φ = 21404202946.

The previous prime is 21404202899. The next prime is 21404203033. The reversal of 21404202947 is 74920240412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21404202947 - 2⁸ = 21404202691 is a prime.

It is not a weakly prime, because it can be changed into another prime (21404202047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10702101473 + 10702101474.

It is an arithmetic number, because the mean of its divisors is an integer number (10702101474).

Almost surely, 2^21404202947 is an apocalyptic number.

21404202947 is a deficient number, since it is larger than the sum of its proper divisors (1).

21404202947 is an equidigital number, since it uses as much as digits as its factorization.

21404202947 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32256, while the sum is 35.

The spelling of 21404202947 in words is "twenty-one billion, four hundred four million, two hundred two thousand, nine hundred forty-seven".