81087630 has 128 divisors (see below), whose sum is σ = 228372480. Its totient is φ = 18247680.

The previous prime is 81087623. The next prime is 81087631. The reversal of 81087630 is 3678018.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 81087591 and 81087600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81087631) 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 63 ways as a sum of consecutive naturals, for example, 229534 + ... + 229886.

It is an arithmetic number, because the mean of its divisors is an integer number (1784160).

Almost surely, 2^81087630 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81087630, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114186240).

81087630 is an abundant number, since it is smaller than the sum of its proper divisors (147284850).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81087630 is a wasteful number, since it uses less digits than its factorization.

81087630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 81087630 is about 9004.8670173412. The cubic root of 81087630 is about 432.8308448957.

The spelling of 81087630 in words is "eighty-one million, eighty-seven thousand, six hundred thirty".