21370047 has 8 divisors (see below), whose sum is σ = 28553856. Its totient is φ = 14216472.

The previous prime is 21370039. The next prime is 21370049. The reversal of 21370047 is 74007312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21370047 - 2³ = 21370039 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21369999 and 21370026.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21370049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5853 + ... + 8774.

It is an arithmetic number, because the mean of its divisors is an integer number (3569232).

Almost surely, 2^21370047 is an apocalyptic number.

21370047 is a deficient number, since it is larger than the sum of its proper divisors (7183809).

21370047 is a wasteful number, since it uses less digits than its factorization.

21370047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15117.

The product of its (nonzero) digits is 1176, while the sum is 24.

The square root of 21370047 is about 4622.7748160602. The cubic root of 21370047 is about 277.5035175270.

Adding to 21370047 its reverse (74007312), we get a palindrome (95377359).

The spelling of 21370047 in words is "twenty-one million, three hundred seventy thousand, forty-seven".