81789250 has 32 divisors (see below), whose sum is σ = 153653760. Its totient is φ = 32599600.

The previous prime is 81789233. The next prime is 81789263. The reversal of 81789250 is 5298718.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 119409 + ... + 120091.

It is an arithmetic number, because the mean of its divisors is an integer number (4801680).

Almost surely, 2^81789250 is an apocalyptic number.

81789250 is a deficient number, since it is larger than the sum of its proper divisors (71864510).

81789250 is a wasteful number, since it uses less digits than its factorization.

81789250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1179 (or 1169 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 40.

The square root of 81789250 is about 9043.7409295048. The cubic root of 81789250 is about 434.0756343509.

The spelling of 81789250 in words is "eighty-one million, seven hundred eighty-nine thousand, two hundred fifty".