21612520447541 has 8 divisors (see below), whose sum is σ = 22555271703744. Its totient is φ = 20670025562560.

The previous prime is 21612520447489. The next prime is 21612520447579. The reversal of 21612520447541 is 14574402521612.

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 21612520447541 - 2¹⁸ = 21612520185397 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21612520447492 and 21612520447501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21612520440541) 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, 63920516 + ... + 64257741.

It is an arithmetic number, because the mean of its divisors is an integer number (2819408962968).

Almost surely, 2^{21612520447541} is an apocalyptic number.

It is an amenable number.

21612520447541 is a deficient number, since it is larger than the sum of its proper divisors (942751256203).

21612520447541 is a wasteful number, since it uses less digits than its factorization.

21612520447541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128185611.

The product of its (nonzero) digits is 537600, while the sum is 44.

The spelling of 21612520447541 in words is "twenty-one trillion, six hundred twelve billion, five hundred twenty million, four hundred forty-seven thousand, five hundred forty-one".