21047094 has 16 divisors (see below), whose sum is σ = 46771440. Its totient is φ = 7015680.

The previous prime is 21047077. The next prime is 21047099. The reversal of 21047094 is 49074012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21047099) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 194827 + ... + 194934.

It is an arithmetic number, because the mean of its divisors is an integer number (2923215).

Almost surely, 2^21047094 is an apocalyptic number.

21047094 is an abundant number, since it is smaller than the sum of its proper divisors (25724346).

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

21047094 is a wasteful number, since it uses less digits than its factorization.

21047094 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 389772 (or 389766 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 21047094 is about 4587.7111940487. The cubic root of 21047094 is about 276.0984998145.

The spelling of 21047094 in words is "twenty-one million, forty-seven thousand, ninety-four".