81107553 has 16 divisors (see below), whose sum is σ = 111315456. Its totient is φ = 52498560.

The previous prime is 81107549. The next prime is 81107557. The reversal of 81107553 is 35570118.

It is an interprime number because it is at equal distance from previous prime (81107549) and next prime (81107557).

It is not a de Polignac number, because 81107553 - 2² = 81107549 is a prime.

It is a super-3 number, since 3×81107553³ (a number of 25 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81107553.

It is not an unprimeable number, because it can be changed into a prime (81107557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25951 + ... + 28907.

It is an arithmetic number, because the mean of its divisors is an integer number (6957216).

Almost surely, 2^81107553 is an apocalyptic number.

It is an amenable number.

81107553 is a deficient number, since it is larger than the sum of its proper divisors (30207903).

81107553 is a wasteful number, since it uses less digits than its factorization.

81107553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3224.

The product of its (nonzero) digits is 4200, while the sum is 30.

The square root of 81107553 is about 9005.9731845037. The cubic root of 81107553 is about 432.8662904287.

The spelling of 81107553 in words is "eighty-one million, one hundred seven thousand, five hundred fifty-three".