21124469 has 2 divisors, whose sum is σ = 21124470. Its totient is φ = 21124468.

The previous prime is 21124463. The next prime is 21124487. The reversal of 21124469 is 96442112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13764100 + 7360369 = 3710^2 + 2713^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21124469 is a prime.

It is a super-2 number, since 2×21124469² = 892486381063922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21124463) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10562234 + 10562235.

It is an arithmetic number, because the mean of its divisors is an integer number (10562235).

Almost surely, 2^21124469 is an apocalyptic number.

It is an amenable number.

21124469 is a deficient number, since it is larger than the sum of its proper divisors (1).

21124469 is an equidigital number, since it uses as much as digits as its factorization.

21124469 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 29.

The square root of 21124469 is about 4596.1363121648. The cubic root of 21124469 is about 276.4364244678.

The spelling of 21124469 in words is "twenty-one million, one hundred twenty-four thousand, four hundred sixty-nine".