8131772054781 has 24 divisors (see below), whose sum is σ = 11778915917184. Its totient is φ = 5405942566080.

The previous prime is 8131772054729. The next prime is 8131772054803. The reversal of 8131772054781 is 1874502771318.

8131772054781 is a `hidden beast` number, since 8 + 1 + 3 + 1 + 77 + 20 + 547 + 8 + 1 = 666.

It is not a de Polignac number, because 8131772054781 - 2⁹ = 8131772054269 is a prime.

It is a super-2 number, since 2×8131772054781² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8131772054711) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40463910 + ... + 40664376.

It is an arithmetic number, because the mean of its divisors is an integer number (490788163216).

Almost surely, 2^{8131772054781} is an apocalyptic number.

It is an amenable number.

8131772054781 is a deficient number, since it is larger than the sum of its proper divisors (3647143862403).

8131772054781 is a wasteful number, since it uses less digits than its factorization.

8131772054781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213121 (or 213118 counting only the distinct ones).

The product of its (nonzero) digits is 2634240, while the sum is 54.

The spelling of 8131772054781 in words is "eight trillion, one hundred thirty-one billion, seven hundred seventy-two million, fifty-four thousand, seven hundred eighty-one".