21761130247 has 2 divisors, whose sum is σ = 21761130248. Its totient is φ = 21761130246.

The previous prime is 21761130221. The next prime is 21761130299. The reversal of 21761130247 is 74203116712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21761130247 - 2³¹ = 19613646599 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21761230247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10880565123 + 10880565124.

It is an arithmetic number, because the mean of its divisors is an integer number (10880565124).

Almost surely, 2^21761130247 is an apocalyptic number.

21761130247 is a deficient number, since it is larger than the sum of its proper divisors (1).

21761130247 is an equidigital number, since it uses as much as digits as its factorization.

21761130247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14112, while the sum is 34.

Adding to 21761130247 its reverse (74203116712), we get a palindrome (95964246959).

The spelling of 21761130247 in words is "twenty-one billion, seven hundred sixty-one million, one hundred thirty thousand, two hundred forty-seven".