21451142 has 8 divisors (see below), whose sum is σ = 32280456. Its totient is φ = 10690992.

The previous prime is 21451141. The next prime is 21451147. The reversal of 21451142 is 24115412.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21451141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16508 + ... + 17759.

It is an arithmetic number, because the mean of its divisors is an integer number (4035057).

Almost surely, 2^21451142 is an apocalyptic number.

21451142 is a deficient number, since it is larger than the sum of its proper divisors (10829314).

21451142 is a wasteful number, since it uses less digits than its factorization.

21451142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34582.

The product of its digits is 320, while the sum is 20.

The square root of 21451142 is about 4631.5377575920. The cubic root of 21451142 is about 277.8540976543.

Adding to 21451142 its reverse (24115412), we get a palindrome (45566554).

The spelling of 21451142 in words is "twenty-one million, four hundred fifty-one thousand, one hundred forty-two".