7821856641131 has 8 divisors (see below), whose sum is σ = 8619434152560. Its totient is φ = 7052264305632.

The previous prime is 7821856641113. The next prime is 7821856641143. The reversal of 7821856641131 is 1311466581287.

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

It is a de Polignac number, because none of the positive numbers 2^k-7821856641131 is a prime.

It is a super-2 number, since 2×7821856641131² (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 (7821856641331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6996293396 + ... + 6996294513.

It is an arithmetic number, because the mean of its divisors is an integer number (1077429269070).

Almost surely, 2^{7821856641131} is an apocalyptic number.

7821856641131 is a deficient number, since it is larger than the sum of its proper divisors (797577511429).

7821856641131 is a wasteful number, since it uses less digits than its factorization.

7821856641131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13992587965.

The product of its digits is 1935360, while the sum is 53.

The spelling of 7821856641131 in words is "seven trillion, eight hundred twenty-one billion, eight hundred fifty-six million, six hundred forty-one thousand, one hundred thirty-one".