21113031473 has 2 divisors, whose sum is σ = 21113031474. Its totient is φ = 21113031472.

The previous prime is 21113031431. The next prime is 21113031479. The reversal of 21113031473 is 37413031112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17215276849 + 3897754624 = 131207^2 + 62432^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21113031473 is a prime.

It is not a weakly prime, because it can be changed into another prime (21113031479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556515736 + 10556515737.

It is an arithmetic number, because the mean of its divisors is an integer number (10556515737).

Almost surely, 2^21113031473 is an apocalyptic number.

It is an amenable number.

21113031473 is a deficient number, since it is larger than the sum of its proper divisors (1).

21113031473 is an equidigital number, since it uses as much as digits as its factorization.

21113031473 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1512, while the sum is 26.

Adding to 21113031473 its reverse (37413031112), we get a palindrome (58526062585).

The spelling of 21113031473 in words is "twenty-one billion, one hundred thirteen million, thirty-one thousand, four hundred seventy-three".