81465689088 has 440 divisors, whose sum is σ = 279850643072. Its totient is φ = 23123460096.

The previous prime is 81465689047. The next prime is 81465689089. The reversal of 81465689088 is 88098656418.

81465689088 is a `hidden beast` number, since 8 + 1 + 465 + 6 + 8 + 90 + 88 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (81465689089) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 112056981 + ... + 112057707.

Almost surely, 2^81465689088 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81465689088, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139925321536).

81465689088 is an abundant number, since it is smaller than the sum of its proper divisors (198384953984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81465689088 is a wasteful number, since it uses less digits than its factorization.

81465689088 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 959 (or 932 counting only the distinct ones).

The product of its (nonzero) digits is 26542080, while the sum is 63.

The spelling of 81465689088 in words is "eighty-one billion, four hundred sixty-five million, six hundred eighty-nine thousand, eighty-eight".