81878760 has 96 divisors (see below), whose sum is σ = 269568000. Its totient is φ = 21550464.

The previous prime is 81878759. The next prime is 81878777. The reversal of 81878760 is 6787818.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27001 + ... + 29879.

It is an arithmetic number, because the mean of its divisors is an integer number (2808000).

Almost surely, 2^81878760 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 81878760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134784000).

81878760 is an abundant number, since it is smaller than the sum of its proper divisors (187689240).

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

81878760 is a wasteful number, since it uses less digits than its factorization.

81878760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2975 (or 2968 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 45.

The square root of 81878760 is about 9048.6883027321. The cubic root of 81878760 is about 434.2339271367.

The spelling of 81878760 in words is "eighty-one million, eight hundred seventy-eight thousand, seven hundred sixty".