21223048 has 64 divisors (see below), whose sum is σ = 50181120. Its totient is φ = 8174400.

The previous prime is 21223009. The next prime is 21223051. The reversal of 21223048 is 84032212.

It is a Harshad number since it is a multiple of its sum of digits (22).

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 15 ways as a sum of consecutive naturals, for example, 80565 + ... + 80827.

It is an arithmetic number, because the mean of its divisors is an integer number (784080).

Almost surely, 2^21223048 is an apocalyptic number.

21223048 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21223048, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25090560).

21223048 is an abundant number, since it is smaller than the sum of its proper divisors (28958072).

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

21223048 is a wasteful number, since it uses less digits than its factorization.

21223048 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418 (or 414 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 21223048 is about 4606.8479462643. The cubic root of 21223048 is about 276.8657614366.

It can be divided in two parts, 2 and 1223048, that multiplied together give a square (2446096 = 1564²).

The spelling of 21223048 in words is "twenty-one million, two hundred twenty-three thousand, forty-eight".