81240898 has 32 divisors (see below), whose sum is σ = 128241792. Its totient is φ = 38572800.

The previous prime is 81240893. The next prime is 81240923. The reversal of 81240898 is 89804218.

It is a self number, because there is not a number n which added to its sum of digits gives 81240898.

It is not an unprimeable number, because it can be changed into a prime (81240893) 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, 718890 + ... + 719002.

It is an arithmetic number, because the mean of its divisors is an integer number (4007556).

Almost surely, 2^81240898 is an apocalyptic number.

81240898 is a deficient number, since it is larger than the sum of its proper divisors (47000894).

81240898 is a wasteful number, since it uses less digits than its factorization.

81240898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330.

The product of its (nonzero) digits is 36864, while the sum is 40.

The square root of 81240898 is about 9013.3732864006. The cubic root of 81240898 is about 433.1033787160.

The spelling of 81240898 in words is "eighty-one million, two hundred forty thousand, eight hundred ninety-eight".