21507532274561 has 8 divisors (see below), whose sum is σ = 21526232892864. Its totient is φ = 21488832228240.

The previous prime is 21507532274519. The next prime is 21507532274573. The reversal of 21507532274561 is 16547223570512.

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 21507532274561 - 2⁶ = 21507532274497 is a prime.

It is a super-3 number, since 3×21507532274561³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21507532274581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115441295 + ... + 115627451.

It is an arithmetic number, because the mean of its divisors is an integer number (2690779111608).

Almost surely, 2^{21507532274561} is an apocalyptic number.

It is an amenable number.

21507532274561 is a deficient number, since it is larger than the sum of its proper divisors (18700618303).

21507532274561 is a wasteful number, since it uses less digits than its factorization.

21507532274561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285991.

The product of its (nonzero) digits is 3528000, while the sum is 50.

The spelling of 21507532274561 in words is "twenty-one trillion, five hundred seven billion, five hundred thirty-two million, two hundred seventy-four thousand, five hundred sixty-one".