81370680 has 64 divisors (see below), whose sum is σ = 246391200. Its totient is φ = 21496320.

The previous prime is 81370651. The next prime is 81370699. The reversal of 81370680 is 8607318.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9970 + ... + 16190.

Almost surely, 2^81370680 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 81370680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123195600).

81370680 is an abundant number, since it is smaller than the sum of its proper divisors (165020520).

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

81370680 is a wasteful number, since it uses less digits than its factorization.

81370680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6344 (or 6340 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 81370680 is about 9020.5698267903. The cubic root of 81370680 is about 433.3338829710. Note that the first 3 decimals are identical.

Adding to 81370680 its reverse (8607318), we get a palindrome (89977998).

The spelling of 81370680 in words is "eighty-one million, three hundred seventy thousand, six hundred eighty".