21255328547 has 2 divisors, whose sum is σ = 21255328548. Its totient is φ = 21255328546.

The previous prime is 21255328541. The next prime is 21255328553. The reversal of 21255328547 is 74582355212.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (21255328541) and next prime (21255328553).

It is a cyclic number.

It is not a de Polignac number, because 21255328547 - 2⁶ = 21255328483 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21255328498 and 21255328507.

It is not a weakly prime, because it can be changed into another prime (21255328541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10627664273 + 10627664274.

It is an arithmetic number, because the mean of its divisors is an integer number (10627664274).

Almost surely, 2^21255328547 is an apocalyptic number.

21255328547 is a deficient number, since it is larger than the sum of its proper divisors (1).

21255328547 is an equidigital number, since it uses as much as digits as its factorization.

21255328547 is an evil number, because the sum of its binary digits is even.

The product of its digits is 672000, while the sum is 44.

The spelling of 21255328547 in words is "twenty-one billion, two hundred fifty-five million, three hundred twenty-eight thousand, five hundred forty-seven".