21343542 has 32 divisors (see below), whose sum is σ = 46756224. Its totient is φ = 6441600.

The previous prime is 21343519. The next prime is 21343579. The reversal of 21343542 is 24534312.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 21358 + ... + 22334.

It is an arithmetic number, because the mean of its divisors is an integer number (1461132).

Almost surely, 2^21343542 is an apocalyptic number.

21343542 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21343542 is an abundant number, since it is smaller than the sum of its proper divisors (25412682).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21343542 is a wasteful number, since it uses less digits than its factorization.

21343542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1324.

The product of its digits is 2880, while the sum is 24.

The square root of 21343542 is about 4619.9071419240. The cubic root of 21343542 is about 277.3887420238.

Adding to 21343542 its reverse (24534312), we get a palindrome (45877854).

The spelling of 21343542 in words is "twenty-one million, three hundred forty-three thousand, five hundred forty-two".