72891081899 has 4 divisors (see below), whose sum is σ = 73355356464. Its totient is φ = 72426807336.

The previous prime is 72891081881. The next prime is 72891081997. The reversal of 72891081899 is 99818019827.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99818019827 = 131 ⋅761969617.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72891081899 is a prime.

It is a super-3 number, since 3×72891081899³ (a number of 34 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72891081869) 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, 232137047 + ... + 232137360.

It is an arithmetic number, because the mean of its divisors is an integer number (18338839116).

Almost surely, 2^72891081899 is an apocalyptic number.

72891081899 is a deficient number, since it is larger than the sum of its proper divisors (464274565).

72891081899 is a wasteful number, since it uses less digits than its factorization.

72891081899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 464274564.

The product of its (nonzero) digits is 5225472, while the sum is 62.

The spelling of 72891081899 in words is "seventy-two billion, eight hundred ninety-one million, eighty-one thousand, eight hundred ninety-nine".