81387033 has 32 divisors (see below), whose sum is σ = 136421376. Its totient is φ = 42009408.

The previous prime is 81386999. The next prime is 81387049. The reversal of 81387033 is 33078318.

It is not a de Polignac number, because 81387033 - 2⁹ = 81386521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81386985 and 81387003.

It is not an unprimeable number, because it can be changed into a prime (81387083) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9660 + ... + 16002.

It is an arithmetic number, because the mean of its divisors is an integer number (4263168).

Almost surely, 2^81387033 is an apocalyptic number.

It is an amenable number.

81387033 is a deficient number, since it is larger than the sum of its proper divisors (55034343).

81387033 is a wasteful number, since it uses less digits than its factorization.

81387033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6413.

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 81387033 is about 9021.4762095790. The cubic root of 81387033 is about 433.3629099471.

The spelling of 81387033 in words is "eighty-one million, three hundred eighty-seven thousand, thirty-three".