81183663 has 12 divisors (see below), whose sum is σ = 127925928. Its totient is φ = 49202160.

The previous prime is 81183623. The next prime is 81183667. The reversal of 81183663 is 36638118.

It is not a de Polignac number, because 81183663 - 2⁸ = 81183407 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81183667) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 409920 + ... + 410117.

It is an arithmetic number, because the mean of its divisors is an integer number (10660494).

Almost surely, 2^81183663 is an apocalyptic number.

81183663 is a deficient number, since it is larger than the sum of its proper divisors (46742265).

81183663 is a wasteful number, since it uses less digits than its factorization.

81183663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 820054 (or 820051 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 81183663 is about 9010.1977225808. The cubic root of 81183663 is about 433.0016463125.

It can be divided in two parts, 8118 and 3663, that added together give a triangular number (11781 = T₁₅₃).

The spelling of 81183663 in words is "eighty-one million, one hundred eighty-three thousand, six hundred sixty-three".