81055280 has 40 divisors (see below), whose sum is σ = 189084624. Its totient is φ = 32313600.

The previous prime is 81055279. The next prime is 81055309. The reversal of 81055280 is 8255018.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24950 + ... + 28010.

Almost surely, 2^81055280 is an apocalyptic number.

81055280 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81055280 is an abundant number, since it is smaller than the sum of its proper divisors (108029344).

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

81055280 is a wasteful number, since it uses less digits than its factorization.

81055280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3405 (or 3399 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 29.

The square root of 81055280 is about 9003.0705873052. The cubic root of 81055280 is about 432.7732777909.

The spelling of 81055280 in words is "eighty-one million, fifty-five thousand, two hundred eighty".