21047027 has 4 divisors (see below), whose sum is σ = 21343536. Its totient is φ = 20750520.

The previous prime is 21047017. The next prime is 21047051. The reversal of 21047027 is 72074012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21047027 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21046993 and 21047011.

It is not an unprimeable number, because it can be changed into a prime (21047017) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 148148 + ... + 148289.

It is an arithmetic number, because the mean of its divisors is an integer number (5335884).

Almost surely, 2^21047027 is an apocalyptic number.

21047027 is a deficient number, since it is larger than the sum of its proper divisors (296509).

21047027 is an equidigital number, since it uses as much as digits as its factorization.

21047027 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296508.

The product of its (nonzero) digits is 784, while the sum is 23.

The square root of 21047027 is about 4587.7038919268. The cubic root of 21047027 is about 276.0982068427.

The spelling of 21047027 in words is "twenty-one million, forty-seven thousand, twenty-seven".