21047026 has 32 divisors (see below), whose sum is σ = 42392448. Its totient is φ = 7568640.

The previous prime is 21047017. The next prime is 21047051. The reversal of 21047026 is 62074012.

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

It is a junction number, because it is equal to n+sod(n) for n = 21046988 and 21047006.

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, 3255 + ... + 7258.

It is an arithmetic number, because the mean of its divisors is an integer number (1324764).

Almost surely, 2^21047026 is an apocalyptic number.

21047026 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21047026 is an abundant number, since it is smaller than the sum of its proper divisors (21345422).

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

21047026 is a wasteful number, since it uses less digits than its factorization.

21047026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10546.

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 21047026 is about 4587.7037829398. The cubic root of 21047026 is about 276.0982024699.

The spelling of 21047026 in words is "twenty-one million, forty-seven thousand, twenty-six".