81051608 has 96 divisors (see below), whose sum is σ = 179518080. Its totient is φ = 34214400.

The previous prime is 81051601. The next prime is 81051611. The reversal of 81051608 is 80615018.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81051601) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1110260 + ... + 1110332.

It is an arithmetic number, because the mean of its divisors is an integer number (1869980).

Almost surely, 2^81051608 is an apocalyptic number.

81051608 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81051608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89759040).

81051608 is an abundant number, since it is smaller than the sum of its proper divisors (98466472).

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

81051608 is a wasteful number, since it uses less digits than its factorization.

81051608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169 (or 154 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 29.

The square root of 81051608 is about 9002.8666545718. The cubic root of 81051608 is about 432.7667424672.

The spelling of 81051608 in words is "eighty-one million, fifty-one thousand, six hundred eight".