21534842 has 8 divisors (see below), whose sum is σ = 36916896. Its totient is φ = 9229212.

The previous prime is 21534841. The next prime is 21534889. The reversal of 21534842 is 24843512.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (21534841) 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, 769088 + ... + 769115.

It is an arithmetic number, because the mean of its divisors is an integer number (4614612).

Almost surely, 2^21534842 is an apocalyptic number.

21534842 is a deficient number, since it is larger than the sum of its proper divisors (15382054).

21534842 is a wasteful number, since it uses less digits than its factorization.

21534842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1538212.

The product of its digits is 7680, while the sum is 29.

The square root of 21534842 is about 4640.5648363103. The cubic root of 21534842 is about 278.2150140321.

The spelling of 21534842 in words is "twenty-one million, five hundred thirty-four thousand, eight hundred forty-two".