21735981107 has 2 divisors, whose sum is σ = 21735981108. Its totient is φ = 21735981106.

The previous prime is 21735981031. The next prime is 21735981131. The reversal of 21735981107 is 70118953712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21735981107 - 2¹⁶ = 21735915571 is a prime.

It is not a weakly prime, because it can be changed into another prime (21735081107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10867990553 + 10867990554.

It is an arithmetic number, because the mean of its divisors is an integer number (10867990554).

Almost surely, 2^21735981107 is an apocalyptic number.

21735981107 is a deficient number, since it is larger than the sum of its proper divisors (1).

21735981107 is an equidigital number, since it uses as much as digits as its factorization.

21735981107 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 105840, while the sum is 44.

The spelling of 21735981107 in words is "twenty-one billion, seven hundred thirty-five million, nine hundred eighty-one thousand, one hundred seven".