21796278 has 80 divisors (see below), whose sum is σ = 54451440. Its totient is φ = 5795328.

The previous prime is 21796253. The next prime is 21796279. The reversal of 21796278 is 87269712.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21796279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 244858 + ... + 244946.

It is an arithmetic number, because the mean of its divisors is an integer number (680643).

Almost surely, 2^21796278 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21796278, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27225720).

21796278 is an abundant number, since it is smaller than the sum of its proper divisors (32655162).

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

21796278 is an equidigital number, since it uses as much as digits as its factorization.

21796278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139 (or 118 counting only the distinct ones).

The product of its digits is 84672, while the sum is 42.

The square root of 21796278 is about 4668.6484125494. The cubic root of 21796278 is about 279.3363449163.

The spelling of 21796278 in words is "twenty-one million, seven hundred ninety-six thousand, two hundred seventy-eight".