81841903 has 8 divisors (see below), whose sum is σ = 96150096. Its totient is φ = 68678400.

The previous prime is 81841897. The next prime is 81841951. The reversal of 81841903 is 30914818.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 81841903 - 2⁵ = 81841871 is a prime.

It is a super-2 number, since 2×81841903² = 13396194173322818, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81841603) 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, 286018 + ... + 286303.

It is an arithmetic number, because the mean of its divisors is an integer number (12018762).

Almost surely, 2^81841903 is an apocalyptic number.

81841903 is a deficient number, since it is larger than the sum of its proper divisors (14308193).

81841903 is a wasteful number, since it uses less digits than its factorization.

81841903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 572345.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 81841903 is about 9046.6514799676. The cubic root of 81841903 is about 434.1687618366.

The spelling of 81841903 in words is "eighty-one million, eight hundred forty-one thousand, nine hundred three".