81413451231 has 32 divisors (see below), whose sum is σ = 132832120320. Its totient is φ = 43293398016.

The previous prime is 81413451199. The next prime is 81413451257. The reversal of 81413451231 is 13215431418.

It is not a de Polignac number, because 81413451231 - 2⁵ = 81413451199 is a prime.

It is a super-2 number, since 2×81413451231² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81413451192 and 81413451201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81413450231) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1249401 + ... + 1312946.

It is an arithmetic number, because the mean of its divisors is an integer number (4151003760).

Almost surely, 2^81413451231 is an apocalyptic number.

81413451231 is a deficient number, since it is larger than the sum of its proper divisors (51418669089).

81413451231 is a wasteful number, since it uses less digits than its factorization.

81413451231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2562463.

The product of its digits is 11520, while the sum is 33.

Adding to 81413451231 its reverse (13215431418), we get a palindrome (94628882649).

The spelling of 81413451231 in words is "eighty-one billion, four hundred thirteen million, four hundred fifty-one thousand, two hundred thirty-one".