81000003 has 32 divisors (see below), whose sum is σ = 127148032. Its totient is φ = 44906400.

The previous prime is 81000001. The next prime is 81000013. The reversal of 81000003 is 30000018.

It is not a de Polignac number, because 81000003 - 2¹ = 81000001 is a prime.

It is a super-2 number, since 2×81000003² = 13122000972000018, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81000001) 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, 244548 + ... + 244878.

It is an arithmetic number, because the mean of its divisors is an integer number (3973376).

Almost surely, 2^81000003 is an apocalyptic number.

81000003 is a deficient number, since it is larger than the sum of its proper divisors (46148029).

81000003 is a wasteful number, since it uses less digits than its factorization.

81000003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 655.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 81000003 is about 9000.0001666667. Note that the first 3 decimals coincide. The cubic root of 81000003 is about 432.6748764339.

It can be divided in two parts, 8100000 and 3, that multiplied together give a 5-th power (24300000 = 30⁵).

The spelling of 81000003 in words is "eighty-one million, three", and thus it is an aban number and an uban number.