21933678 has 64 divisors (see below), whose sum is σ = 50061312. Its totient is φ = 6359040.

The previous prime is 21933677. The next prime is 21933683. The reversal of 21933678 is 87633912.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21933671) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 113550 + ... + 113742.

It is an arithmetic number, because the mean of its divisors is an integer number (782208).

Almost surely, 2^21933678 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21933678, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25030656).

21933678 is an abundant number, since it is smaller than the sum of its proper divisors (28127634).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21933678 is a wasteful number, since it uses less digits than its factorization.

21933678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 289.

The product of its digits is 54432, while the sum is 39.

The square root of 21933678 is about 4683.3404744904. The cubic root of 21933678 is about 279.9220786574.

The spelling of 21933678 in words is "twenty-one million, nine hundred thirty-three thousand, six hundred seventy-eight".