21425342 has 8 divisors (see below), whose sum is σ = 32221800. Its totient is φ = 10684744.

The previous prime is 21425333. The next prime is 21425347. The reversal of 21425342 is 24352412.

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 (21425347) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12992 + ... + 14547.

It is an arithmetic number, because the mean of its divisors is an integer number (4027725).

Almost surely, 2^21425342 is an apocalyptic number.

21425342 is a deficient number, since it is larger than the sum of its proper divisors (10796458).

21425342 is a wasteful number, since it uses less digits than its factorization.

21425342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27930.

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

The square root of 21425342 is about 4628.7516675665. The cubic root of 21425342 is about 277.7426581852.

Adding to 21425342 its reverse (24352412), we get a palindrome (45777754).

The spelling of 21425342 in words is "twenty-one million, four hundred twenty-five thousand, three hundred forty-two".