81040250 has 16 divisors (see below), whose sum is σ = 151707816. Its totient is φ = 32416000.

The previous prime is 81040237. The next prime is 81040259. The reversal of 81040250 is 5204018.

It can be written as a sum of positive squares in 4 ways, for example, as 52085089 + 28955161 = 7217^2 + 5381^2 .

It is not an unprimeable number, because it can be changed into a prime (81040259) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 161831 + ... + 162330.

Almost surely, 2^81040250 is an apocalyptic number.

81040250 is a deficient number, since it is larger than the sum of its proper divisors (70667566).

81040250 is a wasteful number, since it uses less digits than its factorization.

81040250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324178 (or 324168 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 81040250 is about 9002.2358333916. The cubic root of 81040250 is about 432.7465265644.

Adding to 81040250 its reverse (5204018), we get a palindrome (86244268).

The spelling of 81040250 in words is "eighty-one million, forty thousand, two hundred fifty".