81939603 has 8 divisors (see below), whose sum is σ = 112777216. Its totient is φ = 52864200.

The previous prime is 81939601. The next prime is 81939617. The reversal of 81939603 is 30693918.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81939603 - 2¹ = 81939601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81939601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 440443 + ... + 440628.

It is an arithmetic number, because the mean of its divisors is an integer number (14097152).

Almost surely, 2^81939603 is an apocalyptic number.

81939603 is a deficient number, since it is larger than the sum of its proper divisors (30837613).

81939603 is a wasteful number, since it uses less digits than its factorization.

81939603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 881105.

The product of its (nonzero) digits is 34992, while the sum is 39.

The square root of 81939603 is about 9052.0496573980. The cubic root of 81939603 is about 434.3414582937.

The spelling of 81939603 in words is "eighty-one million, nine hundred thirty-nine thousand, six hundred three".