81340898 has 4 divisors (see below), whose sum is σ = 122011350. Its totient is φ = 40670448.

The previous prime is 81340841. The next prime is 81340901. The reversal of 81340898 is 89804318.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 45064369 + 36276529 = 6713^2 + 6023^2 .

It is a Curzon number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 20335223 + ... + 20335226.

Almost surely, 2^81340898 is an apocalyptic number.

81340898 is a deficient number, since it is larger than the sum of its proper divisors (40670452).

81340898 is a wasteful number, since it uses less digits than its factorization.

81340898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40670451.

The product of its (nonzero) digits is 55296, while the sum is 41.

The square root of 81340898 is about 9018.9188930825. The cubic root of 81340898 is about 433.2810091983.

The spelling of 81340898 in words is "eighty-one million, three hundred forty thousand, eight hundred ninety-eight".