21347347 has 8 divisors (see below), whose sum is σ = 24992352. Its totient is φ = 17851200.

The previous prime is 21347329. The next prime is 21347363. The reversal of 21347347 is 74374312.

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

It is a cyclic number.

It is not a de Polignac number, because 21347347 - 2¹⁹ = 20823059 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21347047) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36904 + ... + 37477.

It is an arithmetic number, because the mean of its divisors is an integer number (3124044).

Almost surely, 2^21347347 is an apocalyptic number.

21347347 is a deficient number, since it is larger than the sum of its proper divisors (3645005).

21347347 is an equidigital number, since it uses as much as digits as its factorization.

21347347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74429.

The product of its digits is 14112, while the sum is 31.

The square root of 21347347 is about 4620.3189283858. The cubic root of 21347347 is about 277.4052247839.

The spelling of 21347347 in words is "twenty-one million, three hundred forty-seven thousand, three hundred forty-seven".