81382693316 has 6 divisors (see below), whose sum is σ = 142419713310. Its totient is φ = 40691346656.

The previous prime is 81382693309. The next prime is 81382693319. The reversal of 81382693316 is 61339628318.

It can be written as a sum of positive squares in only one way, i.e., 81312803716 + 69889600 = 285154^2 + 8360^2 .

It is a super-2 number, since 2×81382693316² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81382693319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10172836661 + ... + 10172836668.

It is an arithmetic number, because the mean of its divisors is an integer number (23736618885).

Almost surely, 2^81382693316 is an apocalyptic number.

It is an amenable number.

81382693316 is a deficient number, since it is larger than the sum of its proper divisors (61037019994).

81382693316 is a wasteful number, since it uses less digits than its factorization.

81382693316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20345673333 (or 20345673331 counting only the distinct ones).

The product of its digits is 1119744, while the sum is 50.

The spelling of 81382693316 in words is "eighty-one billion, three hundred eighty-two million, six hundred ninety-three thousand, three hundred sixteen".