21856070 has 16 divisors (see below), whose sum is σ = 39929328. Its totient is φ = 8611680.

The previous prime is 21856069. The next prime is 21856129. The reversal of 21856070 is 7065812.

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, 15641 + ... + 16980.

It is an arithmetic number, because the mean of its divisors is an integer number (2495583).

Almost surely, 2^21856070 is an apocalyptic number.

21856070 is a deficient number, since it is larger than the sum of its proper divisors (18073258).

21856070 is a wasteful number, since it uses less digits than its factorization.

21856070 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32695.

The product of its (nonzero) digits is 3360, while the sum is 29.

The square root of 21856070 is about 4675.0475933406. The cubic root of 21856070 is about 279.5915387843.

The spelling of 21856070 in words is "twenty-one million, eight hundred fifty-six thousand, seventy".