81388514 has 8 divisors (see below), whose sum is σ = 128508240. Its totient is φ = 38552436.

The previous prime is 81388511. The next prime is 81388519. The reversal of 81388514 is 41588318.

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

It is a super-2 number, since 2×81388514² = 13248180422256392, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (38), and also a Moran number because the ratio is a prime number: 2141803 = 81388514 / (8 + 1 + 3 + 8 + 8 + 5 + 1 + 4).

It is not an unprimeable number, because it can be changed into a prime (81388511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1070864 + ... + 1070939.

It is an arithmetic number, because the mean of its divisors is an integer number (16063530).

Almost surely, 2^81388514 is an apocalyptic number.

81388514 is a deficient number, since it is larger than the sum of its proper divisors (47119726).

81388514 is a wasteful number, since it uses less digits than its factorization.

81388514 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2141824.

The product of its digits is 30720, while the sum is 38.

The square root of 81388514 is about 9021.5582911158. The cubic root of 81388514 is about 433.3655385664.

The spelling of 81388514 in words is "eighty-one million, three hundred eighty-eight thousand, five hundred fourteen".