21242450 has 12 divisors (see below), whose sum is σ = 39511050. Its totient is φ = 8496960.

The previous prime is 21242443. The next prime is 21242461. The reversal of 21242450 is 5424212.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 10543009 + 10699441 = 3247^2 + 3271^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 212375 + ... + 212474.

Almost surely, 2^21242450 is an apocalyptic number.

21242450 is a deficient number, since it is larger than the sum of its proper divisors (18268600).

21242450 is a wasteful number, since it uses less digits than its factorization.

21242450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 424861 (or 424856 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 21242450 is about 4608.9532434166. The cubic root of 21242450 is about 276.9501054855.

Adding to 21242450 its reverse (5424212), we get a palindrome (26666662).

The spelling of 21242450 in words is "twenty-one million, two hundred forty-two thousand, four hundred fifty".