21118524547 has 2 divisors, whose sum is σ = 21118524548. Its totient is φ = 21118524546.

The previous prime is 21118524503. The next prime is 21118524569. The reversal of 21118524547 is 74542581112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21118524547 - 2¹¹ = 21118522499 is a prime.

It is not a weakly prime, because it can be changed into another prime (21118524587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10559262273 + 10559262274.

It is an arithmetic number, because the mean of its divisors is an integer number (10559262274).

Almost surely, 2^21118524547 is an apocalyptic number.

21118524547 is a deficient number, since it is larger than the sum of its proper divisors (1).

21118524547 is an equidigital number, since it uses as much as digits as its factorization.

21118524547 is an evil number, because the sum of its binary digits is even.

The product of its digits is 89600, while the sum is 40.

The spelling of 21118524547 in words is "twenty-one billion, one hundred eighteen million, five hundred twenty-four thousand, five hundred forty-seven".