21475773461 has 2 divisors, whose sum is σ = 21475773462. Its totient is φ = 21475773460.

The previous prime is 21475773443. The next prime is 21475773503. The reversal of 21475773461 is 16437757412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15330154225 + 6145619236 = 123815^2 + 78394^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21475773461 is a prime.

It is a super-2 number, since 2×21475773461² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21475773401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10737886730 + 10737886731.

It is an arithmetic number, because the mean of its divisors is an integer number (10737886731).

Almost surely, 2^21475773461 is an apocalyptic number.

It is an amenable number.

21475773461 is a deficient number, since it is larger than the sum of its proper divisors (1).

21475773461 is an equidigital number, since it uses as much as digits as its factorization.

21475773461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 987840, while the sum is 47.

The spelling of 21475773461 in words is "twenty-one billion, four hundred seventy-five million, seven hundred seventy-three thousand, four hundred sixty-one".