21058047 has 6 divisors (see below), whose sum is σ = 30417192. Its totient is φ = 14038692.

The previous prime is 21058043. The next prime is 21058049. The reversal of 21058047 is 74085012.

It is not a de Polignac number, because 21058047 - 2² = 21058043 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21058047.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21058043) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1169883 + ... + 1169900.

It is an arithmetic number, because the mean of its divisors is an integer number (5069532).

Almost surely, 2^21058047 is an apocalyptic number.

21058047 is a deficient number, since it is larger than the sum of its proper divisors (9359145).

21058047 is a wasteful number, since it uses less digits than its factorization.

21058047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2339789 (or 2339786 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 21058047 is about 4588.9047712935. The cubic root of 21058047 is about 276.1463857987.

The spelling of 21058047 in words is "twenty-one million, fifty-eight thousand, forty-seven".