21398006 has 24 divisors (see below), whose sum is σ = 37739016. Its totient is φ = 9072000.

The previous prime is 21397997. The next prime is 21398017. The reversal of 21398006 is 60089312.

It is a self number, because there is not a number n which added to its sum of digits gives 21398006.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8381 + ... + 10631.

It is an arithmetic number, because the mean of its divisors is an integer number (1572459).

Almost surely, 2^21398006 is an apocalyptic number.

21398006 is a deficient number, since it is larger than the sum of its proper divisors (16341010).

21398006 is a wasteful number, since it uses less digits than its factorization.

21398006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2364 (or 2357 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 21398006 is about 4625.7978771235. The cubic root of 21398006 is about 277.6244865272.

The spelling of 21398006 in words is "twenty-one million, three hundred ninety-eight thousand, six".