81988258 has 8 divisors (see below), whose sum is σ = 134162640. Its totient is φ = 37267380.

The previous prime is 81988243. The next prime is 81988303. The reversal of 81988258 is 85288918.

It is a happy number.

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

It is a plaindrome in base 12.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1863348 + ... + 1863391.

It is an arithmetic number, because the mean of its divisors is an integer number (16770330).

Almost surely, 2^81988258 is an apocalyptic number.

81988258 is a deficient number, since it is larger than the sum of its proper divisors (52174382).

81988258 is a wasteful number, since it uses less digits than its factorization.

81988258 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3726752.

The product of its digits is 368640, while the sum is 49.

The square root of 81988258 is about 9054.7367714363. The cubic root of 81988258 is about 434.4274106351.

The spelling of 81988258 in words is "eighty-one million, nine hundred eighty-eight thousand, two hundred fifty-eight".