21747753251 has 48 divisors (see below), whose sum is σ = 27410353344. Its totient is φ = 17138774016.

The previous prime is 21747753239. The next prime is 21747753257. The reversal of 21747753251 is 15235774712.

It is a de Polignac number, because none of the positive numbers 2^k-21747753251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21747753257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11610251 + ... + 11612123.

It is an arithmetic number, because the mean of its divisors is an integer number (571049028).

Almost surely, 2^21747753251 is an apocalyptic number.

21747753251 is a deficient number, since it is larger than the sum of its proper divisors (5662600093).

21747753251 is a wasteful number, since it uses less digits than its factorization.

21747753251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2220 (or 2213 counting only the distinct ones).

The product of its digits is 411600, while the sum is 44.

The spelling of 21747753251 in words is "twenty-one billion, seven hundred forty-seven million, seven hundred fifty-three thousand, two hundred fifty-one".