21678350 has 24 divisors (see below), whose sum is σ = 40447560. Its totient is φ = 8644320.

The previous prime is 21678347. The next prime is 21678361. The reversal of 21678350 is 5387612.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25736 + ... + 26564.

It is an arithmetic number, because the mean of its divisors is an integer number (1685315).

Almost surely, 2^21678350 is an apocalyptic number.

21678350 is a deficient number, since it is larger than the sum of its proper divisors (18769210).

21678350 is a wasteful number, since it uses less digits than its factorization.

21678350 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1364 (or 1359 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 21678350 is about 4656.0015034362. The cubic root of 21678350 is about 278.8316537721.

The spelling of 21678350 in words is "twenty-one million, six hundred seventy-eight thousand, three hundred fifty".