21001541269 has 2 divisors, whose sum is σ = 21001541270. Its totient is φ = 21001541268.

The previous prime is 21001541257. The next prime is 21001541333. The reversal of 21001541269 is 96214510012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19390562500 + 1610978769 = 139250^2 + 40137^2 .

It is a cyclic number.

It is not a de Polignac number, because 21001541269 - 2²¹ = 20999444117 is a prime.

It is a super-2 number, since 2×21001541269² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21001541269.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21001541369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500770634 + 10500770635.

It is an arithmetic number, because the mean of its divisors is an integer number (10500770635).

Almost surely, 2^21001541269 is an apocalyptic number.

It is an amenable number.

21001541269 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001541269 is an equidigital number, since it uses as much as digits as its factorization.

21001541269 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 31.

The spelling of 21001541269 in words is "twenty-one billion, one million, five hundred forty-one thousand, two hundred sixty-nine".