16540009261 has 2 divisors, whose sum is σ = 16540009262. Its totient is φ = 16540009260.

The previous prime is 16540009259. The next prime is 16540009307. The reversal of 16540009261 is 16290004561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15462922500 + 1077086761 = 124350^2 + 32819^2 .

It is a cyclic number.

It is not a de Polignac number, because 16540009261 - 2¹ = 16540009259 is a prime.

It is a super-2 number, since 2×16540009261² (a number of 21 digits) contains 22 as substring.

Together with 16540009259, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16540009231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8270004630 + 8270004631.

It is an arithmetic number, because the mean of its divisors is an integer number (8270004631).

Almost surely, 2^16540009261 is an apocalyptic number.

It is an amenable number.

16540009261 is a deficient number, since it is larger than the sum of its proper divisors (1).

16540009261 is an equidigital number, since it uses as much as digits as its factorization.

16540009261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960, while the sum is 34.

The spelling of 16540009261 in words is "sixteen billion, five hundred forty million, nine thousand, two hundred sixty-one".