83791385981 has 8 divisors (see below), whose sum is σ = 85866508728. Its totient is φ = 81717760000.

The previous prime is 83791385939. The next prime is 83791386023. The reversal of 83791385981 is 18958319738.

It is an interprime number because it is at equal distance from previous prime (83791385939) and next prime (83791386023).

It can be written as a sum of positive squares in 4 ways, for example, as 11047901881 + 72743484100 = 105109^2 + 269710^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 83791385981 - 2³⁰ = 82717644157 is a prime.

It is a super-2 number, since 2×83791385981² (a number of 23 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 (83791385581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 260420 + ... + 485181.

It is an arithmetic number, because the mean of its divisors is an integer number (10733313591).

Almost surely, 2^83791385981 is an apocalyptic number.

It is an amenable number.

83791385981 is a deficient number, since it is larger than the sum of its proper divisors (2075122747).

83791385981 is a wasteful number, since it uses less digits than its factorization.

83791385981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 748383.

The product of its digits is 13063680, while the sum is 62.

The spelling of 83791385981 in words is "eighty-three billion, seven hundred ninety-one million, three hundred eighty-five thousand, nine hundred eighty-one".