81577292489 has 16 divisors (see below), whose sum is σ = 101744016000. Its totient is φ = 63543432960.

The previous prime is 81577292483. The next prime is 81577292507. The reversal of 81577292489 is 98429277518.

It is a de Polignac number, because none of the positive numbers 2^k-81577292489 is a prime.

It is a Smith number, since the sum of its digits (62) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81577292483) 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, 18977 + ... + 404369.

It is an arithmetic number, because the mean of its divisors is an integer number (6359001000).

Almost surely, 2^81577292489 is an apocalyptic number.

It is an amenable number.

81577292489 is a deficient number, since it is larger than the sum of its proper divisors (20166723511).

81577292489 is a wasteful number, since it uses less digits than its factorization.

81577292489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388160.

The product of its digits is 20321280, while the sum is 62.

The spelling of 81577292489 in words is "eighty-one billion, five hundred seventy-seven million, two hundred ninety-two thousand, four hundred eighty-nine".