81149170731 has 16 divisors (see below), whose sum is σ = 110849169024. Its totient is φ = 52777355904.

The previous prime is 81149170721. The next prime is 81149170741. The reversal of 81149170731 is 13707194118.

It is an interprime number because it is at equal distance from previous prime (81149170721) and next prime (81149170741).

It is not a de Polignac number, because 81149170731 - 2⁷ = 81149170603 is a prime.

It is a super-2 number, since 2×81149170731² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81149170721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 273646 + ... + 487011.

It is an arithmetic number, because the mean of its divisors is an integer number (6928073064).

Almost surely, 2^81149170731 is an apocalyptic number.

81149170731 is a deficient number, since it is larger than the sum of its proper divisors (29699998293).

81149170731 is a wasteful number, since it uses less digits than its factorization.

81149170731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 761530.

The product of its (nonzero) digits is 42336, while the sum is 42.

The spelling of 81149170731 in words is "eighty-one billion, one hundred forty-nine million, one hundred seventy thousand, seven hundred thirty-one".