21651560105361 has 16 divisors (see below), whose sum is σ = 30389588216640. Its totient is φ = 13674024383040.

The previous prime is 21651560105347. The next prime is 21651560105363. The reversal of 21651560105361 is 16350106515612.

It is not a de Polignac number, because 21651560105361 - 2⁶ = 21651560105297 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21651560105363) 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 in 15 ways as a sum of consecutive naturals, for example, 7740310 + ... + 10159503.

It is an arithmetic number, because the mean of its divisors is an integer number (1899349263540).

Almost surely, 2^{21651560105361} is an apocalyptic number.

It is an amenable number.

21651560105361 is a deficient number, since it is larger than the sum of its proper divisors (8738028111279).

21651560105361 is a wasteful number, since it uses less digits than its factorization.

21651560105361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17921056.

The product of its (nonzero) digits is 162000, while the sum is 42.

The spelling of 21651560105361 in words is "twenty-one trillion, six hundred fifty-one billion, five hundred sixty million, one hundred five thousand, three hundred sixty-one".