81182461 has 4 divisors (see below), whose sum is σ = 81567424. Its totient is φ = 80797500.

The previous prime is 81182447. The next prime is 81182467. The reversal of 81182461 is 16428118.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81182461 - 2⁷ = 81182333 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81182467) 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 3 ways as a sum of consecutive naturals, for example, 192165 + ... + 192586.

It is an arithmetic number, because the mean of its divisors is an integer number (20391856).

Almost surely, 2^81182461 is an apocalyptic number.

It is an amenable number.

81182461 is a deficient number, since it is larger than the sum of its proper divisors (384963).

81182461 is a wasteful number, since it uses less digits than its factorization.

81182461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384962.

The product of its digits is 3072, while the sum is 31.

The square root of 81182461 is about 9010.1310201351. The cubic root of 81182461 is about 432.9995093040. Note that the first 3 decimals are identical.

The spelling of 81182461 in words is "eighty-one million, one hundred eighty-two thousand, four hundred sixty-one".