81394011 has 32 divisors (see below), whose sum is σ = 128286720. Its totient is φ = 50827392.

The previous prime is 81394009. The next prime is 81394021. The reversal of 81394011 is 11049318.

It is not a de Polignac number, because 81394011 - 2¹ = 81394009 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (81394021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 175566 + ... + 176028.

It is an arithmetic number, because the mean of its divisors is an integer number (4008960).

Almost surely, 2^81394011 is an apocalyptic number.

81394011 is a deficient number, since it is larger than the sum of its proper divisors (46892709).

81394011 is a wasteful number, since it uses less digits than its factorization.

81394011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 872 (or 866 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 81394011 is about 9021.8629450907. The cubic root of 81394011 is about 433.3752948846.

The spelling of 81394011 in words is "eighty-one million, three hundred ninety-four thousand, eleven".