21961948873 has 2 divisors, whose sum is σ = 21961948874. Its totient is φ = 21961948872.

The previous prime is 21961948859. The next prime is 21961948891. The reversal of 21961948873 is 37884916912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11137003024 + 10824945849 = 105532^2 + 104043^2 .

It is a cyclic number.

It is not a de Polignac number, because 21961948873 - 2¹³ = 21961940681 is a prime.

It is not a weakly prime, because it can be changed into another prime (21961948373) 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, 10980974436 + 10980974437.

It is an arithmetic number, because the mean of its divisors is an integer number (10980974437).

Almost surely, 2^21961948873 is an apocalyptic number.

It is an amenable number.

21961948873 is a deficient number, since it is larger than the sum of its proper divisors (1).

21961948873 is an equidigital number, since it uses as much as digits as its factorization.

21961948873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5225472, while the sum is 58.

The spelling of 21961948873 in words is "twenty-one billion, nine hundred sixty-one million, nine hundred forty-eight thousand, eight hundred seventy-three".