81238927247 has 8 divisors (see below), whose sum is σ = 86344901760. Its totient is φ = 76215976920.

The previous prime is 81238927219. The next prime is 81238927283. The reversal of 81238927247 is 74272983218.

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 81238927247 - 2⁶ = 81238927183 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81238947247) 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, 20754029 + ... + 20757942.

It is an arithmetic number, because the mean of its divisors is an integer number (10793112720).

Almost surely, 2^81238927247 is an apocalyptic number.

81238927247 is a deficient number, since it is larger than the sum of its proper divisors (5105974513).

81238927247 is a wasteful number, since it uses less digits than its factorization.

81238927247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41512093.

The product of its digits is 2709504, while the sum is 53.

The spelling of 81238927247 in words is "eighty-one billion, two hundred thirty-eight million, nine hundred twenty-seven thousand, two hundred forty-seven".