81070000 has 150 divisors (see below), whose sum is σ = 218964284. Its totient is φ = 29040000.

The previous prime is 81069977. The next prime is 81070027. The reversal of 81070000 is 7018.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 1209967 + ... + 1210033.

Almost surely, 2^81070000 is an apocalyptic number.

81070000 is a gapful number since it is divisible by the number (80) 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 81070000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109482142).

81070000 is an abundant number, since it is smaller than the sum of its proper divisors (137894284).

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

81070000 is a wasteful number, since it uses less digits than its factorization.

81070000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117 (or 85 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 81070000 is about 9003.8880490597. Note that the first 3 decimals coincide. The cubic root of 81070000 is about 432.7994740570.

Adding to 81070000 its reverse (7018), we get a palindrome (81077018).

The spelling of 81070000 in words is "eighty-one million, seventy thousand".