81864949867238 has 8 divisors (see below), whose sum is σ = 122797617231432. Its totient is φ = 40932410790096.

The previous prime is 81864949867159. The next prime is 81864949867303. The reversal of 81864949867238 is 83276894946818.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30460220 + ... + 33038687.

It is an arithmetic number, because the mean of its divisors is an integer number (15349702153929).

Almost surely, 2^{81864949867238} is an apocalyptic number.

81864949867238 is a deficient number, since it is larger than the sum of its proper divisors (40932667364194).

81864949867238 is a wasteful number, since it uses less digits than its factorization.

81864949867238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64143526.

The product of its digits is 8026324992, while the sum is 83.

The spelling of 81864949867238 in words is "eighty-one trillion, eight hundred sixty-four billion, nine hundred forty-nine million, eight hundred sixty-seven thousand, two hundred thirty-eight".