21707461 has 2 divisors, whose sum is σ = 21707462. Its totient is φ = 21707460.

The previous prime is 21707437. The next prime is 21707473. The reversal of 21707461 is 16470712.

21707461 = 3294² + 3295².

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10857025 + 10850436 = 3295^2 + 3294^2 .

It is a cyclic number.

It is not a de Polignac number, because 21707461 - 2⁵ = 21707429 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21707401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10853730 + 10853731.

It is an arithmetic number, because the mean of its divisors is an integer number (10853731).

Almost surely, 2^21707461 is an apocalyptic number.

21707461 is the 3295-th centered square number.

It is an amenable number.

21707461 is a deficient number, since it is larger than the sum of its proper divisors (1).

21707461 is an equidigital number, since it uses as much as digits as its factorization.

21707461 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2352, while the sum is 28.

The square root of 21707461 is about 4659.1266348963. The cubic root of 21707461 is about 278.9564086176.

The spelling of 21707461 in words is "twenty-one million, seven hundred seven thousand, four hundred sixty-one".