81115145149 has 8 divisors (see below), whose sum is σ = 81930486528. Its totient is φ = 80300043600.

The previous prime is 81115145147. The next prime is 81115145179. The reversal of 81115145149 is 94154151118.

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

It is a cyclic number.

It is not a de Polignac number, because 81115145149 - 2¹ = 81115145147 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81115145147) 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, 663484 + ... + 776170.

It is an arithmetic number, because the mean of its divisors is an integer number (10241310816).

Almost surely, 2^81115145149 is an apocalyptic number.

It is an amenable number.

81115145149 is a deficient number, since it is larger than the sum of its proper divisors (815341379).

81115145149 is a wasteful number, since it uses less digits than its factorization.

81115145149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119915.

The product of its digits is 28800, while the sum is 40.

The spelling of 81115145149 in words is "eighty-one billion, one hundred fifteen million, one hundred forty-five thousand, one hundred forty-nine".