21727550547613 has 2 divisors, whose sum is σ = 21727550547614. Its totient is φ = 21727550547612.

The previous prime is 21727550547607. The next prime is 21727550547617. The reversal of 21727550547613 is 31674505572712.

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., 21641271472324 + 86279075289 = 4652018^2 + 293733^2 .

It is a cyclic number.

It is not a de Polignac number, because 21727550547613 - 2²⁹ = 21727013676701 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21727550547617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10863775273806 + 10863775273807.

It is an arithmetic number, because the mean of its divisors is an integer number (10863775273807).

Almost surely, 2^{21727550547613} is an apocalyptic number.

It is an amenable number.

21727550547613 is a deficient number, since it is larger than the sum of its proper divisors (1).

21727550547613 is an equidigital number, since it uses as much as digits as its factorization.

21727550547613 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12348000, while the sum is 55.

The spelling of 21727550547613 in words is "twenty-one trillion, seven hundred twenty-seven billion, five hundred fifty million, five hundred forty-seven thousand, six hundred thirteen".