21347207 has 8 divisors (see below), whose sum is σ = 24450432. Its totient is φ = 18257400.

The previous prime is 21347201. The next prime is 21347213. The reversal of 21347207 is 70274312.

It is an interprime number because it is at equal distance from previous prime (21347201) and next prime (21347213).

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

It is not a de Polignac number, because 21347207 - 2¹⁰ = 21346183 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21347201) 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, 332 + ... + 6542.

It is an arithmetic number, because the mean of its divisors is an integer number (3056304).

Almost surely, 2^21347207 is an apocalyptic number.

21347207 is a deficient number, since it is larger than the sum of its proper divisors (3103225).

21347207 is an equidigital number, since it uses as much as digits as its factorization.

21347207 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6709.

The product of its (nonzero) digits is 2352, while the sum is 26.

The square root of 21347207 is about 4620.3037778917. The cubic root of 21347207 is about 277.4046183570.

The spelling of 21347207 in words is "twenty-one million, three hundred forty-seven thousand, two hundred seven".