21325442 has 4 divisors (see below), whose sum is σ = 31988166. Its totient is φ = 10662720.

The previous prime is 21325441. The next prime is 21325457. The reversal of 21325442 is 24452312.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 11282881 + 10042561 = 3359^2 + 3169^2 .

It is not an unprimeable number, because it can be changed into a prime (21325441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5331359 + ... + 5331362.

Almost surely, 2^21325442 is an apocalyptic number.

21325442 is a deficient number, since it is larger than the sum of its proper divisors (10662724).

21325442 is a wasteful number, since it uses less digits than its factorization.

21325442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10662723.

The product of its digits is 1920, while the sum is 23.

The square root of 21325442 is about 4617.9478126111. The cubic root of 21325442 is about 277.3103083670.

Adding to 21325442 its reverse (24452312), we get a palindrome (45777754).

The spelling of 21325442 in words is "twenty-one million, three hundred twenty-five thousand, four hundred forty-two".