21498461 has 2 divisors, whose sum is σ = 21498462. Its totient is φ = 21498460.

The previous prime is 21498439. The next prime is 21498511. The reversal of 21498461 is 16489412.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14707225 + 6791236 = 3835^2 + 2606^2 .

It is a cyclic number.

It is not a de Polignac number, because 21498461 - 2¹⁸ = 21236317 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21498431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10749230 + 10749231.

It is an arithmetic number, because the mean of its divisors is an integer number (10749231).

Almost surely, 2^21498461 is an apocalyptic number.

It is an amenable number.

21498461 is a deficient number, since it is larger than the sum of its proper divisors (1).

21498461 is an equidigital number, since it uses as much as digits as its factorization.

21498461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 35.

The square root of 21498461 is about 4636.6432901400. The cubic root of 21498461 is about 278.0582534102.

The spelling of 21498461 in words is "twenty-one million, four hundred ninety-eight thousand, four hundred sixty-one".