21027145054549 has 2 divisors, whose sum is σ = 21027145054550. Its totient is φ = 21027145054548.

The previous prime is 21027145054471. The next prime is 21027145054579. The reversal of 21027145054549 is 94545054172012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18235846419025 + 2791298635524 = 4270345^2 + 1670718^2 .

It is a cyclic number.

It is not a de Polignac number, because 21027145054549 - 2¹³ = 21027145046357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21027145054579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10513572527274 + 10513572527275.

It is an arithmetic number, because the mean of its divisors is an integer number (10513572527275).

Almost surely, 2^{21027145054549} is an apocalyptic number.

It is an amenable number.

21027145054549 is a deficient number, since it is larger than the sum of its proper divisors (1).

21027145054549 is an equidigital number, since it uses as much as digits as its factorization.

21027145054549 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016000, while the sum is 49.

The spelling of 21027145054549 in words is "twenty-one trillion, twenty-seven billion, one hundred forty-five million, fifty-four thousand, five hundred forty-nine".