21461542 has 8 divisors (see below), whose sum is σ = 32250600. Its totient is φ = 10711344.

The previous prime is 21461533. The next prime is 21461543. The reversal of 21461542 is 24516412.

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 (21461543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8292 + ... + 10567.

It is an arithmetic number, because the mean of its divisors is an integer number (4031325).

Almost surely, 2^21461542 is an apocalyptic number.

21461542 is a deficient number, since it is larger than the sum of its proper divisors (10789058).

21461542 is a wasteful number, since it uses less digits than its factorization.

21461542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19430.

The product of its digits is 1920, while the sum is 25.

The square root of 21461542 is about 4632.6603588003. The cubic root of 21461542 is about 277.8989937216.

Adding to 21461542 its reverse (24516412), we get a palindrome (45977954).

The spelling of 21461542 in words is "twenty-one million, four hundred sixty-one thousand, five hundred forty-two".