81438927 has 8 divisors (see below), whose sum is σ = 108705840. Its totient is φ = 54232320.

The previous prime is 81438923. The next prime is 81438937. The reversal of 81438927 is 72983418.

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

It is not a de Polignac number, because 81438927 - 2² = 81438923 is a prime.

It is a super-2 number, since 2×81438927² = 13264597661822658, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81438923) 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, 11824 + ... + 17397.

It is an arithmetic number, because the mean of its divisors is an integer number (13588230).

Almost surely, 2^81438927 is an apocalyptic number.

81438927 is a deficient number, since it is larger than the sum of its proper divisors (27266913).

81438927 is a wasteful number, since it uses less digits than its factorization.

81438927 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30153.

The product of its digits is 96768, while the sum is 42.

The square root of 81438927 is about 9024.3518880859. The cubic root of 81438927 is about 433.4549973305.

The spelling of 81438927 in words is "eighty-one million, four hundred thirty-eight thousand, nine hundred twenty-seven".