21436342 has 4 divisors (see below), whose sum is σ = 32154516. Its totient is φ = 10718170.

The previous prime is 21436339. The next prime is 21436343. The reversal of 21436342 is 24363412.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21436343) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5359084 + ... + 5359087.

It is an arithmetic number, because the mean of its divisors is an integer number (8038629).

Almost surely, 2^21436342 is an apocalyptic number.

21436342 is a deficient number, since it is larger than the sum of its proper divisors (10718174).

21436342 is a wasteful number, since it uses less digits than its factorization.

21436342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10718173.

The product of its digits is 3456, while the sum is 25.

The square root of 21436342 is about 4629.9397404286. The cubic root of 21436342 is about 277.7901820713.

Adding to 21436342 its reverse (24363412), we get a palindrome (45799754).

The spelling of 21436342 in words is "twenty-one million, four hundred thirty-six thousand, three hundred forty-two".