81933604 has 6 divisors (see below), whose sum is σ = 143383814. Its totient is φ = 40966800.

The previous prime is 81933583. The next prime is 81933623. The reversal of 81933604 is 40633918.

It can be written as a sum of positive squares in only one way, i.e., 76597504 + 5336100 = 8752^2 + 2310^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 81933604.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10241697 + ... + 10241704.

Almost surely, 2^81933604 is an apocalyptic number.

It is an amenable number.

81933604 is a deficient number, since it is larger than the sum of its proper divisors (61450210).

81933604 is a wasteful number, since it uses less digits than its factorization.

81933604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20483405 (or 20483403 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 81933604 is about 9051.7182899160. The cubic root of 81933604 is about 434.3308582993.

The spelling of 81933604 in words is "eighty-one million, nine hundred thirty-three thousand, six hundred four".