21550431020531 has 8 divisors (see below), whose sum is σ = 24645150948864. Its totient is φ = 18459732823560.

The previous prime is 21550431020519. The next prime is 21550431020593. The reversal of 21550431020531 is 13502013405512.

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

It is not a de Polignac number, because 21550431020531 - 2¹⁴ = 21550431004147 is a prime.

It is a super-2 number, since 2×21550431020531² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21550431020501) 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, 1005421355 + ... + 1005442788.

It is an arithmetic number, because the mean of its divisors is an integer number (3080643868608).

Almost surely, 2^{21550431020531} is an apocalyptic number.

21550431020531 is a deficient number, since it is larger than the sum of its proper divisors (3094719928333).

21550431020531 is a wasteful number, since it uses less digits than its factorization.

21550431020531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2010865681.

The product of its (nonzero) digits is 18000, while the sum is 32.

The spelling of 21550431020531 in words is "twenty-one trillion, five hundred fifty billion, four hundred thirty-one million, twenty thousand, five hundred thirty-one".