16531187233781 has 16 divisors (see below), whose sum is σ = 18290410333056. Its totient is φ = 14814750720000.

The previous prime is 16531187233747. The next prime is 16531187233811. The reversal of 16531187233781 is 18733278113561.

It is not a de Polignac number, because 16531187233781 - 2²² = 16531183039477 is a prime.

It is a super-2 number, since 2×16531187233781² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16531187233721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4621001 + ... + 7376721.

It is an arithmetic number, because the mean of its divisors is an integer number (1143150645816).

Almost surely, 2^{16531187233781} is an apocalyptic number.

16531187233781 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16531187233781 is a deficient number, since it is larger than the sum of its proper divisors (1759223099275).

16531187233781 is a wasteful number, since it uses less digits than its factorization.

16531187233781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2763484.

The product of its digits is 5080320, while the sum is 56.

The spelling of 16531187233781 in words is "sixteen trillion, five hundred thirty-one billion, one hundred eighty-seven million, two hundred thirty-three thousand, seven hundred eighty-one".