81238927 has 16 divisors (see below), whose sum is σ = 106617600. Its totient is φ = 59970240.

The previous prime is 81238891. The next prime is 81238957. The reversal of 81238927 is 72983218.

It is not a de Polignac number, because 81238927 - 2¹¹ = 81236879 is a prime.

It is a super-2 number, since 2×81238927² = 13199526520222658, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81238927.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81238957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26302 + ... + 29227.

It is an arithmetic number, because the mean of its divisors is an integer number (6663600).

Almost surely, 2^81238927 is an apocalyptic number.

81238927 is a deficient number, since it is larger than the sum of its proper divisors (25378673).

81238927 is a wasteful number, since it uses less digits than its factorization.

81238927 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55566.

The product of its digits is 48384, while the sum is 40.

The square root of 81238927 is about 9013.2639482043. The cubic root of 81238927 is about 433.0998761548.

The spelling of 81238927 in words is "eighty-one million, two hundred thirty-eight thousand, nine hundred twenty-seven".