81133548 has 24 divisors (see below), whose sum is σ = 190990128. Its totient is φ = 26804736.

The previous prime is 81133543. The next prime is 81133567. The reversal of 81133548 is 84533118.

It is a super-2 number, since 2×81133548² = 13165305222136608, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81133543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28561 + ... + 31272.

It is an arithmetic number, because the mean of its divisors is an integer number (7957922).

Almost surely, 2^81133548 is an apocalyptic number.

It is an amenable number.

81133548 is an abundant number, since it is smaller than the sum of its proper divisors (109856580).

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

81133548 is a wasteful number, since it uses less digits than its factorization.

81133548 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59953 (or 59951 counting only the distinct ones).

The product of its digits is 11520, while the sum is 33.

The square root of 81133548 is about 9007.4162777125. The cubic root of 81133548 is about 432.9125300898.

The spelling of 81133548 in words is "eighty-one million, one hundred thirty-three thousand, five hundred forty-eight".