81732506 has 12 divisors (see below), whose sum is σ = 123299946. Its totient is φ = 40633560.

The previous prime is 81732493. The next prime is 81732517. The reversal of 81732506 is 60523718.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 68475625 + 13256881 = 8275^2 + 3641^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 218936 + ... + 219308.

Almost surely, 2^81732506 is an apocalyptic number.

81732506 is a deficient number, since it is larger than the sum of its proper divisors (41567440).

81732506 is an equidigital number, since it uses as much as digits as its factorization.

81732506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1037 (or 706 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 81732506 is about 9040.6031878410. The cubic root of 81732506 is about 433.9752263461.

The spelling of 81732506 in words is "eighty-one million, seven hundred thirty-two thousand, five hundred six".