21356342 has 16 divisors (see below), whose sum is σ = 38538240. Its totient is φ = 8670888.

The previous prime is 21356341. The next prime is 21356347. The reversal of 21356342 is 24365312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21356341) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39878 + ... + 40409.

It is an arithmetic number, because the mean of its divisors is an integer number (2408640).

Almost surely, 2^21356342 is an apocalyptic number.

21356342 is a deficient number, since it is larger than the sum of its proper divisors (17181898).

21356342 is a wasteful number, since it uses less digits than its factorization.

21356342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80315.

The product of its digits is 4320, while the sum is 26.

The square root of 21356342 is about 4621.2922435180. The cubic root of 21356342 is about 277.4441821558. Note that the first 3 decimals are identical.

The spelling of 21356342 in words is "twenty-one million, three hundred fifty-six thousand, three hundred forty-two".