21660535151641 has 8 divisors (see below), whose sum is σ = 22410754806600. Its totient is φ = 20910535806720.

The previous prime is 21660535151627. The next prime is 21660535151653. The reversal of 21660535151641 is 14615153506612.

It can be written as a sum of positive squares in 4 ways, for example, as 2885992790041 + 18774542361600 = 1698821^2 + 4332960^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21660535151641 - 2¹³ = 21660535143449 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21660535151591 and 21660535151600.

It is not an unprimeable number, because it can be changed into a prime (21660535151611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54877456 + ... + 55270753.

It is an arithmetic number, because the mean of its divisors is an integer number (2801344350825).

Almost surely, 2^{21660535151641} is an apocalyptic number.

It is an amenable number.

21660535151641 is a deficient number, since it is larger than the sum of its proper divisors (750219654959).

21660535151641 is a wasteful number, since it uses less digits than its factorization.

21660535151641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110155019.

The product of its (nonzero) digits is 648000, while the sum is 46.

The spelling of 21660535151641 in words is "twenty-one trillion, six hundred sixty billion, five hundred thirty-five million, one hundred fifty-one thousand, six hundred forty-one".