81180490 has 8 divisors (see below), whose sum is σ = 146124900. Its totient is φ = 32472192.

The previous prime is 81180487. The next prime is 81180499. The reversal of 81180490 is 9408118.

It can be written as a sum of positive squares in 2 ways, for example, as 78623689 + 2556801 = 8867^2 + 1599^2 .

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

It is not an unprimeable number, because it can be changed into a prime (81180499) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4059015 + ... + 4059034.

Almost surely, 2^81180490 is an apocalyptic number.

81180490 is a deficient number, since it is larger than the sum of its proper divisors (64944410).

81180490 is a wasteful number, since it uses less digits than its factorization.

81180490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8118056.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 81180490 is about 9010.0216425933. The cubic root of 81180490 is about 432.9960050621.

The spelling of 81180490 in words is "eighty-one million, one hundred eighty thousand, four hundred ninety".