21847047751 has 4 divisors (see below), whose sum is σ = 21847563472. Its totient is φ = 21846532032.

The previous prime is 21847047731. The next prime is 21847047757. The reversal of 21847047751 is 15774074812.

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 21847047751 - 2⁷ = 21847047623 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 (21847047757) 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, 188010 + ... + 281143.

It is an arithmetic number, because the mean of its divisors is an integer number (5461890868).

Almost surely, 2^21847047751 is an apocalyptic number.

21847047751 is a deficient number, since it is larger than the sum of its proper divisors (515721).

21847047751 is an equidigital number, since it uses as much as digits as its factorization.

21847047751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515720.

The product of its (nonzero) digits is 439040, while the sum is 46.

The spelling of 21847047751 in words is "twenty-one billion, eight hundred forty-seven million, forty-seven thousand, seven hundred fifty-one".