81071011408 has 40 divisors (see below), whose sum is σ = 166846327848. Its totient is φ = 38029135872.

The previous prime is 81071011361. The next prime is 81071011421. The reversal of 81071011408 is 80411017018.

It can be written as a sum of positive squares in 4 ways, for example, as 35141184 + 81035870224 = 5928^2 + 284668^2 .

It is a super-2 number, since 2×81071011408² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81071011408.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 390991 + ... + 561262.

Almost surely, 2^81071011408 is an apocalyptic number.

It is an amenable number.

81071011408 is an abundant number, since it is smaller than the sum of its proper divisors (85775316440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81071011408 is a wasteful number, since it uses less digits than its factorization.

81071011408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 952591 (or 952585 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 31.

The spelling of 81071011408 in words is "eighty-one billion, seventy-one million, eleven thousand, four hundred eight".