81128610 has 24 divisors (see below), whose sum is σ = 210934620. Its totient is φ = 21634272.

The previous prime is 81128609. The next prime is 81128629. The reversal of 81128610 is 1682118.

It can be written as a sum of positive squares in 2 ways, for example, as 79548561 + 1580049 = 8919^2 + 1257^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 450625 + ... + 450804.

Almost surely, 2^81128610 is an apocalyptic number.

81128610 is an abundant number, since it is smaller than the sum of its proper divisors (129806010).

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

81128610 is a wasteful number, since it uses less digits than its factorization.

81128610 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 901442 (or 901439 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 27.

The square root of 81128610 is about 9007.1421660813. The cubic root of 81128610 is about 432.9037471819.

The spelling of 81128610 in words is "eighty-one million, one hundred twenty-eight thousand, six hundred ten".