81323404 has 6 divisors (see below), whose sum is σ = 142315964. Its totient is φ = 40661700.

The previous prime is 81323383. The next prime is 81323419. The reversal of 81323404 is 40432318.

It is a super-2 number, since 2×81323404² = 13226992076294432, which contains 22 as substring.

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 as a sum of consecutive naturals, namely, 10165422 + ... + 10165429.

Almost surely, 2^81323404 is an apocalyptic number.

It is an amenable number.

81323404 is a deficient number, since it is larger than the sum of its proper divisors (60992560).

81323404 is a wasteful number, since it uses less digits than its factorization.

81323404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20330855 (or 20330853 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 81323404 is about 9017.9489907628. The cubic root of 81323404 is about 433.2499450325.

The spelling of 81323404 in words is "eighty-one million, three hundred twenty-three thousand, four hundred four".