21001283461 has 2 divisors, whose sum is σ = 21001283462. Its totient is φ = 21001283460.

The previous prime is 21001283437. The next prime is 21001283473. The reversal of 21001283461 is 16438210012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19502122500 + 1499160961 = 139650^2 + 38719^2 .

It is a cyclic number.

It is not a de Polignac number, because 21001283461 - 2⁹ = 21001282949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21001283431) 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, 10500641730 + 10500641731.

It is an arithmetic number, because the mean of its divisors is an integer number (10500641731).

Almost surely, 2^21001283461 is an apocalyptic number.

It is an amenable number.

21001283461 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001283461 is an equidigital number, since it uses as much as digits as its factorization.

21001283461 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 28.

Adding to 21001283461 its reverse (16438210012), we get a palindrome (37439493473).

The spelling of 21001283461 in words is "twenty-one billion, one million, two hundred eighty-three thousand, four hundred sixty-one".