131666320731 has 12 divisors (see below), whose sum is σ = 192965517416. Its totient is φ = 79797769920.

The previous prime is 131666320711. The next prime is 131666320769. The reversal of 131666320731 is 137023666131.

It is not a de Polignac number, because 131666320731 - 2⁵ = 131666320699 is a prime.

It is a super-2 number, since 2×131666320731² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 131666320731.

It is not an unprimeable number, because it can be changed into a prime (131666320711) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 181358206 + ... + 181358931.

Almost surely, 2^131666320731 is an apocalyptic number.

131666320731 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

131666320731 is a deficient number, since it is larger than the sum of its proper divisors (61299196685).

131666320731 is a wasteful number, since it uses less digits than its factorization.

131666320731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362717162 (or 362717151 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 39.

Adding to 131666320731 its reverse (137023666131), we get a palindrome (268689986862).

The spelling of 131666320731 in words is "one hundred thirty-one billion, six hundred sixty-six million, three hundred twenty thousand, seven hundred thirty-one".