21419478 has 64 divisors (see below), whose sum is σ = 49593600. Its totient is φ = 6934248.

The previous prime is 21419467. The next prime is 21419491. The reversal of 21419478 is 87491412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 258025 + ... + 258107.

It is an arithmetic number, because the mean of its divisors is an integer number (774900).

Almost surely, 2^21419478 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21419478, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24796800).

21419478 is an abundant number, since it is smaller than the sum of its proper divisors (28174122).

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

21419478 is an frugal number, since it uses more digits than its factorization.

21419478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165 (or 147 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 21419478 is about 4628.1181920949. The cubic root of 21419478 is about 277.7173169863.

The spelling of 21419478 in words is "twenty-one million, four hundred nineteen thousand, four hundred seventy-eight".