81078894 has 96 divisors (see below), whose sum is σ = 201618144. Its totient is φ = 24261120.

The previous prime is 81078889. The next prime is 81078917. The reversal of 81078894 is 49887018.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 258882 + ... + 259194.

It is an arithmetic number, because the mean of its divisors is an integer number (2100189).

Almost surely, 2^81078894 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81078894, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100809072).

81078894 is an abundant number, since it is smaller than the sum of its proper divisors (120539250).

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

81078894 is a wasteful number, since it uses less digits than its factorization.

81078894 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384 (or 372 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The square root of 81078894 is about 9004.3819332589. The cubic root of 81078894 is about 432.8153006174.

The spelling of 81078894 in words is "eighty-one million, seventy-eight thousand, eight hundred ninety-four".