21419928 has 48 divisors (see below), whose sum is σ = 58629480. Its totient is φ = 7064064.

The previous prime is 21419927. The next prime is 21419933. The reversal of 21419928 is 82991412.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 21419892 and 21419901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21419927) 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 11 ways as a sum of consecutive naturals, for example, 5451 + ... + 8517.

Almost surely, 2^21419928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21419928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29314740).

21419928 is an abundant number, since it is smaller than the sum of its proper divisors (37209552).

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

21419928 is a wasteful number, since it uses less digits than its factorization.

21419928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3176 (or 3169 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 21419928 is about 4628.1668077112. The cubic root of 21419928 is about 277.7192618192.

The spelling of 21419928 in words is "twenty-one million, four hundred nineteen thousand, nine hundred twenty-eight".