21382426 has 32 divisors (see below), whose sum is σ = 35925120. Its totient is φ = 9482304.

The previous prime is 21382423. The next prime is 21382441. The reversal of 21382426 is 62428312.

It is a junction number, because it is equal to n+sod(n) for n = 21382394 and 21382403.

It is not an unprimeable number, because it can be changed into a prime (21382423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81171 + ... + 81433.

It is an arithmetic number, because the mean of its divisors is an integer number (1122660).

Almost surely, 2^21382426 is an apocalyptic number.

21382426 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21382426 is a deficient number, since it is larger than the sum of its proper divisors (14542694).

21382426 is a wasteful number, since it uses less digits than its factorization.

21382426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390.

The product of its digits is 4608, while the sum is 28.

The square root of 21382426 is about 4624.1135366684. The cubic root of 21382426 is about 277.5570902208.

The spelling of 21382426 in words is "twenty-one million, three hundred eighty-two thousand, four hundred twenty-six".