21434278 has 8 divisors (see below), whose sum is σ = 32175360. Its totient is φ = 10709160.

The previous prime is 21434269. The next prime is 21434279. The reversal of 21434278 is 87243412.

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 (21434279) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 283 + ... + 6553.

It is an arithmetic number, because the mean of its divisors is an integer number (4021920).

Almost surely, 2^21434278 is an apocalyptic number.

21434278 is a deficient number, since it is larger than the sum of its proper divisors (10741082).

21434278 is a wasteful number, since it uses less digits than its factorization.

21434278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7982.

The product of its digits is 10752, while the sum is 31.

The square root of 21434278 is about 4629.7168379934. The cubic root of 21434278 is about 277.7812661014.

It can be divided in two parts, 21434 and 278, that added together give a palindrome (21712).

The spelling of 21434278 in words is "twenty-one million, four hundred thirty-four thousand, two hundred seventy-eight".