21606470 has 16 divisors (see below), whose sum is σ = 39070080. Its totient is φ = 8602944.

The previous prime is 21606469. The next prime is 21606491. The reversal of 21606470 is 7460612.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2615 + ... + 7074.

It is an arithmetic number, because the mean of its divisors is an integer number (2441880).

Almost surely, 2^21606470 is an apocalyptic number.

21606470 is a deficient number, since it is larger than the sum of its proper divisors (17463610).

21606470 is a wasteful number, since it uses less digits than its factorization.

21606470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9919.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 21606470 is about 4648.2760245063. The cubic root of 21606470 is about 278.5231337962.

The spelling of 21606470 in words is "twenty-one million, six hundred six thousand, four hundred seventy".