21486738473641 has 27 divisors (see below), whose sum is σ = 25133574634077. Its totient is φ = 18315494919960.

The previous prime is 21486738473623. The next prime is 21486738473671. The reversal of 21486738473641 is 14637483768412.

The square root of 21486738473641 is 4635379.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 21486738473641 - 2¹⁵ = 21486738440873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21486738473621) 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 26 ways as a sum of consecutive naturals, for example, 6197499990 + ... + 6197503456.

Almost surely, 2^{21486738473641} is an apocalyptic number.

21486738473641 is the 4635379-th square number.

21486738473641 is the 2317690-th centered octagonal number.

It is an amenable number.

21486738473641 is a deficient number, since it is larger than the sum of its proper divisors (3646836160436).

21486738473641 is an frugal number, since it uses more digits than its factorization.

21486738473641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7330 (or 3665 counting only the distinct ones).

The product of its digits is 130056192, while the sum is 64.

The spelling of 21486738473641 in words is "twenty-one trillion, four hundred eighty-six billion, seven hundred thirty-eight million, four hundred seventy-three thousand, six hundred forty-one".