81608201249 has 8 divisors (see below), whose sum is σ = 85163339520. Its totient is φ = 78053642656.

The previous prime is 81608201231. The next prime is 81608201261. The reversal of 81608201249 is 94210280618.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81608201249 is a prime.

It is a super-2 number, since 2×81608201249² (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 (81608201219) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 156104 + ... + 433110.

It is an arithmetic number, because the mean of its divisors is an integer number (10645417440).

Almost surely, 2^81608201249 is an apocalyptic number.

It is an amenable number.

81608201249 is a deficient number, since it is larger than the sum of its proper divisors (3555138271).

81608201249 is a wasteful number, since it uses less digits than its factorization.

81608201249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289839.

The product of its (nonzero) digits is 55296, while the sum is 41.

The spelling of 81608201249 in words is "eighty-one billion, six hundred eight million, two hundred one thousand, two hundred forty-nine".