81415558 has 24 divisors (see below), whose sum is σ = 144075024. Its totient is φ = 34398000.

The previous prime is 81415553. The next prime is 81415571. The reversal of 81415558 is 85551418.

It is a super-3 number, since 3×81415558³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81415553) 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 11 ways as a sum of consecutive naturals, for example, 1108 + ... + 12808.

It is an arithmetic number, because the mean of its divisors is an integer number (6003126).

Almost surely, 2^81415558 is an apocalyptic number.

81415558 is a deficient number, since it is larger than the sum of its proper divisors (62659466).

81415558 is a wasteful number, since it uses less digits than its factorization.

81415558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11788 (or 11781 counting only the distinct ones).

The product of its digits is 32000, while the sum is 37.

The square root of 81415558 is about 9023.0570207663. The cubic root of 81415558 is about 433.4135332164.

The spelling of 81415558 in words is "eighty-one million, four hundred fifteen thousand, five hundred fifty-eight".