21525540543 has 24 divisors (see below), whose sum is σ = 33536045088. Its totient is φ = 13225966272.

The previous prime is 21525540523. The next prime is 21525540559. The reversal of 21525540543 is 34504552512.

21525540543 is a `hidden beast` number, since 2 + 1 + 52 + 554 + 0 + 54 + 3 = 666.

It is not a de Polignac number, because 21525540543 - 2⁵ = 21525540511 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21525540498 and 21525540507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21525540523) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 66480 + ... + 217877.

It is an arithmetic number, because the mean of its divisors is an integer number (1397335212).

Almost surely, 2^21525540543 is an apocalyptic number.

21525540543 is a deficient number, since it is larger than the sum of its proper divisors (12010504545).

21525540543 is a wasteful number, since it uses less digits than its factorization.

21525540543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285023 (or 285020 counting only the distinct ones).

The product of its (nonzero) digits is 120000, while the sum is 36.

The spelling of 21525540543 in words is "twenty-one billion, five hundred twenty-five million, five hundred forty thousand, five hundred forty-three".