21531533141255 has 8 divisors (see below), whose sum is σ = 27357712697232. Its totient is φ = 16211977894528.

The previous prime is 21531533141243. The next prime is 21531533141263. The reversal of 21531533141255 is 55214133513512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21531533141255 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 126656077217 + ... + 126656077386.

It is an arithmetic number, because the mean of its divisors is an integer number (3419714087154).

Almost surely, 2^{21531533141255} is an apocalyptic number.

21531533141255 is a deficient number, since it is larger than the sum of its proper divisors (5826179555977).

21531533141255 is a wasteful number, since it uses less digits than its factorization.

21531533141255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253312154625.

The product of its digits is 270000, while the sum is 41.

Adding to 21531533141255 its reverse (55214133513512), we get a palindrome (76745666654767).

The spelling of 21531533141255 in words is "twenty-one trillion, five hundred thirty-one billion, five hundred thirty-three million, one hundred forty-one thousand, two hundred fifty-five".