21470838 has 8 divisors (see below), whose sum is σ = 42941688. Its totient is φ = 7156944.

The previous prime is 21470837. The next prime is 21470843. The reversal of 21470838 is 83807412.

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

21470838 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 21470799 and 21470808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21470831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1789231 + ... + 1789242.

It is an arithmetic number, because the mean of its divisors is an integer number (5367711).

Almost surely, 2^21470838 is an apocalyptic number.

21470838 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21470838 is a wasteful number, since it uses less digits than its factorization.

21470838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3578478.

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 21470838 is about 4633.6635613734. The cubic root of 21470838 is about 277.9391116240.

The spelling of 21470838 in words is "twenty-one million, four hundred seventy thousand, eight hundred thirty-eight".