21244678 has 32 divisors (see below), whose sum is σ = 39606336. Its totient is φ = 8322048.

The previous prime is 21244673. The next prime is 21244681. The reversal of 21244678 is 87644212.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21244673) 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, 20050 + ... + 21082.

It is an arithmetic number, because the mean of its divisors is an integer number (1237698).

Almost surely, 2^21244678 is an apocalyptic number.

21244678 is a deficient number, since it is larger than the sum of its proper divisors (18361658).

21244678 is a wasteful number, since it uses less digits than its factorization.

21244678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1168.

The product of its digits is 21504, while the sum is 34.

The square root of 21244678 is about 4609.1949405509. The cubic root of 21244678 is about 276.9597877218.

The spelling of 21244678 in words is "twenty-one million, two hundred forty-four thousand, six hundred seventy-eight".