21300558973 has 2 divisors, whose sum is σ = 21300558974. Its totient is φ = 21300558972.

The previous prime is 21300558959. The next prime is 21300559043. The reversal of 21300558973 is 37985500312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19016961604 + 2283597369 = 137902^2 + 47787^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21300558973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21300558913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10650279486 + 10650279487.

It is an arithmetic number, because the mean of its divisors is an integer number (10650279487).

Almost surely, 2^21300558973 is an apocalyptic number.

It is an amenable number.

21300558973 is a deficient number, since it is larger than the sum of its proper divisors (1).

21300558973 is an equidigital number, since it uses as much as digits as its factorization.

21300558973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 226800, while the sum is 43.

The spelling of 21300558973 in words is "twenty-one billion, three hundred million, five hundred fifty-eight thousand, nine hundred seventy-three".