21612640541269 has 2 divisors, whose sum is σ = 21612640541270. Its totient is φ = 21612640541268.

The previous prime is 21612640541209. The next prime is 21612640541273. The reversal of 21612640541269 is 96214504621612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16498990991025 + 5113649550244 = 4061895^2 + 2261338^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21612640541269 is a prime.

It is a super-2 number, since 2×21612640541269² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21612640541209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10806320270634 + 10806320270635.

It is an arithmetic number, because the mean of its divisors is an integer number (10806320270635).

Almost surely, 2^{21612640541269} is an apocalyptic number.

It is an amenable number.

21612640541269 is a deficient number, since it is larger than the sum of its proper divisors (1).

21612640541269 is an equidigital number, since it uses as much as digits as its factorization.

21612640541269 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1244160, while the sum is 49.

The spelling of 21612640541269 in words is "twenty-one trillion, six hundred twelve billion, six hundred forty million, five hundred forty-one thousand, two hundred sixty-nine".