81772436088 has 160 divisors (see below), whose sum is σ = 261980991360. Its totient is φ = 23343681600.

The previous prime is 81772436077. The next prime is 81772436111. The reversal of 81772436088 is 88063427718.

It is a happy number.

81772436088 is a `hidden beast` number, since 8 + 1 + 7 + 7 + 24 + 3 + 608 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 5812663 + ... + 5826713.

It is an arithmetic number, because the mean of its divisors is an integer number (1637381196).

Almost surely, 2^81772436088 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 81772436088, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130990495680).

81772436088 is an abundant number, since it is smaller than the sum of its proper divisors (180208555272).

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

81772436088 is a wasteful number, since it uses less digits than its factorization.

81772436088 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15359 (or 15346 counting only the distinct ones).

The product of its (nonzero) digits is 3612672, while the sum is 54.

The spelling of 81772436088 in words is "eighty-one billion, seven hundred seventy-two million, four hundred thirty-six thousand, eighty-eight".