81548840 has 16 divisors (see below), whose sum is σ = 183484980. Its totient is φ = 32619520.

The previous prime is 81548827. The next prime is 81548843. The reversal of 81548840 is 4884518.

It can be written as a sum of positive squares in 2 ways, for example, as 73034116 + 8514724 = 8546^2 + 2918^2 .

It is a junction number, because it is equal to n+sod(n) for n = 81548794 and 81548803.

It is not an unprimeable number, because it can be changed into a prime (81548843) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1019321 + ... + 1019400.

Almost surely, 2^81548840 is an apocalyptic number.

It is an amenable number.

81548840 is an abundant number, since it is smaller than the sum of its proper divisors (101936140).

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

81548840 is a wasteful number, since it uses less digits than its factorization.

81548840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2038732 (or 2038728 counting only the distinct ones).

The product of its (nonzero) digits is 40960, while the sum is 38.

The square root of 81548840 is about 9030.4396349237. The cubic root of 81548840 is about 433.6499119888.

The spelling of 81548840 in words is "eighty-one million, five hundred forty-eight thousand, eight hundred forty".