21047844461207 has 4 divisors (see below), whose sum is σ = 21086749904376. Its totient is φ = 21008939018040.

The previous prime is 21047844461167. The next prime is 21047844461233. The reversal of 21047844461207 is 70216444874012.

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 21047844461207 - 2⁴² = 16649797950103 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 (21047844461807) 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, 19452720773 + ... + 19452721854.

It is an arithmetic number, because the mean of its divisors is an integer number (5271687476094).

Almost surely, 2^{21047844461207} is an apocalyptic number.

21047844461207 is a deficient number, since it is larger than the sum of its proper divisors (38905443169).

21047844461207 is an equidigital number, since it uses as much as digits as its factorization.

21047844461207 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38905443168.

The product of its (nonzero) digits is 2408448, while the sum is 50.

The spelling of 21047844461207 in words is "twenty-one trillion, forty-seven billion, eight hundred forty-four million, four hundred sixty-one thousand, two hundred seven".