72929117081 has 4 divisors (see below), whose sum is σ = 74305138212. Its totient is φ = 71553095952.

The previous prime is 72929117059. The next prime is 72929117101. The reversal of 72929117081 is 18071192927.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18071192927 = 1163 ⋅15538429.

It can be written as a sum of positive squares in 2 ways, for example, as 38657851456 + 34271265625 = 196616^2 + 185125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72929117081 is a prime.

It is a super-2 number, since 2×72929117081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72929117021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 688010486 + ... + 688010591.

It is an arithmetic number, because the mean of its divisors is an integer number (18576284553).

Almost surely, 2^72929117081 is an apocalyptic number.

It is an amenable number.

72929117081 is a deficient number, since it is larger than the sum of its proper divisors (1376021131).

72929117081 is a wasteful number, since it uses less digits than its factorization.

72929117081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1376021130.

The product of its (nonzero) digits is 127008, while the sum is 47.

The spelling of 72929117081 in words is "seventy-two billion, nine hundred twenty-nine million, one hundred seventeen thousand, eighty-one".