21154533213547 has 2 divisors, whose sum is σ = 21154533213548. Its totient is φ = 21154533213546.

The previous prime is 21154533213529. The next prime is 21154533213563. The reversal of 21154533213547 is 74531233545112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21154533213547 - 2²⁷ = 21154398995819 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21154533213497 and 21154533213506.

It is not a weakly prime, because it can be changed into another prime (21154533211547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10577266606773 + 10577266606774.

It is an arithmetic number, because the mean of its divisors is an integer number (10577266606774).

Almost surely, 2^{21154533213547} is an apocalyptic number.

21154533213547 is a deficient number, since it is larger than the sum of its proper divisors (1).

21154533213547 is an equidigital number, since it uses as much as digits as its factorization.

21154533213547 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1512000, while the sum is 46.

Adding to 21154533213547 its reverse (74531233545112), we get a palindrome (95685766758659).

The spelling of 21154533213547 in words is "twenty-one trillion, one hundred fifty-four billion, five hundred thirty-three million, two hundred thirteen thousand, five hundred forty-seven".