21370008 has 64 divisors (see below), whose sum is σ = 59281920. Its totient is φ = 6364800.

The previous prime is 21370001. The next prime is 21370009. The reversal of 21370008 is 80007312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21370001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15441 + ... + 16767.

It is an arithmetic number, because the mean of its divisors is an integer number (926280).

Almost surely, 2^21370008 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21370008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29640960).

21370008 is an abundant number, since it is smaller than the sum of its proper divisors (37911912).

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

21370008 is a wasteful number, since it uses less digits than its factorization.

21370008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1408 (or 1404 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 21370008 is about 4622.7705978125. The cubic root of 21370008 is about 277.5033487137.

The spelling of 21370008 in words is "twenty-one million, three hundred seventy thousand, eight".