81469680 has 80 divisors (see below), whose sum is σ = 263554560. Its totient is φ = 20779264.

The previous prime is 81469673. The next prime is 81469681. The reversal of 81469680 is 8696418.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81469681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1860 + ... + 12899.

It is an arithmetic number, because the mean of its divisors is an integer number (3294432).

Almost surely, 2^81469680 is an apocalyptic number.

81469680 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 81469680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131777280).

81469680 is an abundant number, since it is smaller than the sum of its proper divisors (182084880).

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

81469680 is a wasteful number, since it uses less digits than its factorization.

81469680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14798 (or 14792 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 42.

The square root of 81469680 is about 9026.0556169348. The cubic root of 81469680 is about 433.5095509470.

The spelling of 81469680 in words is "eighty-one million, four hundred sixty-nine thousand, six hundred eighty".