21531055134433 has 8 divisors (see below), whose sum is σ = 23188411622376. Its totient is φ = 19873858857600.

The previous prime is 21531055134431. The next prime is 21531055134461. The reversal of 21531055134433 is 33443155013512.

It can be written as a sum of positive squares in 4 ways, for example, as 481237726369 + 21049817408064 = 693713^2 + 4588008^2 .

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 21531055134433 - 2¹ = 21531055134431 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21531055134431) 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, 39773578 + ... + 40311283.

It is an arithmetic number, because the mean of its divisors is an integer number (2898551452797).

Almost surely, 2^{21531055134433} is an apocalyptic number.

It is an amenable number.

21531055134433 is a deficient number, since it is larger than the sum of its proper divisors (1657356487943).

21531055134433 is a wasteful number, since it uses less digits than its factorization.

21531055134433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80105555.

The product of its (nonzero) digits is 324000, while the sum is 40.

The spelling of 21531055134433 in words is "twenty-one trillion, five hundred thirty-one billion, fifty-five million, one hundred thirty-four thousand, four hundred thirty-three".