21047018207 has 4 divisors (see below), whose sum is σ = 21047457240. Its totient is φ = 21046579176.

The previous prime is 21047018189. The next prime is 21047018243. The reversal of 21047018207 is 70281074012.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21047018207 - 2¹² = 21047014111 is a prime.

It is a super-3 number, since 3×21047018207³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21047015207) 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, 137357 + ... + 246902.

It is an arithmetic number, because the mean of its divisors is an integer number (5261864310).

Almost surely, 2^21047018207 is an apocalyptic number.

21047018207 is a deficient number, since it is larger than the sum of its proper divisors (439033).

21047018207 is an equidigital number, since it uses as much as digits as its factorization.

21047018207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439032.

The product of its (nonzero) digits is 6272, while the sum is 32.

The spelling of 21047018207 in words is "twenty-one billion, forty-seven million, eighteen thousand, two hundred seven".