81382040 has 16 divisors (see below), whose sum is σ = 183109680. Its totient is φ = 32552800.

The previous prime is 81382031. The next prime is 81382057. The reversal of 81382040 is 4028318.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1017236 + ... + 1017315.

It is an arithmetic number, because the mean of its divisors is an integer number (11444355).

Almost surely, 2^81382040 is an apocalyptic number.

It is an amenable number.

81382040 is an abundant number, since it is smaller than the sum of its proper divisors (101727640).

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

81382040 is a wasteful number, since it uses less digits than its factorization.

81382040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2034562 (or 2034558 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 81382040 is about 9021.1994767880. The cubic root of 81382040 is about 433.3540476620.

The spelling of 81382040 in words is "eighty-one million, three hundred eighty-two thousand, forty".