21112405747 has 2 divisors, whose sum is σ = 21112405748. Its totient is φ = 21112405746.

The previous prime is 21112405669. The next prime is 21112405753. The reversal of 21112405747 is 74750421112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21112405747 - 2¹⁹ = 21111881459 is a prime.

It is not a weakly prime, because it can be changed into another prime (21112402747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556202873 + 10556202874.

It is an arithmetic number, because the mean of its divisors is an integer number (10556202874).

Almost surely, 2^21112405747 is an apocalyptic number.

21112405747 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112405747 is an equidigital number, since it uses as much as digits as its factorization.

21112405747 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15680, while the sum is 34.

Adding to 21112405747 its reverse (74750421112), we get a palindrome (95862826859).

The spelling of 21112405747 in words is "twenty-one billion, one hundred twelve million, four hundred five thousand, seven hundred forty-seven".