87881636 has 24 divisors (see below), whose sum is σ = 163399320. Its totient is φ = 41213952.

The previous prime is 87881609. The next prime is 87881639. The reversal of 87881636 is 63618878.

It can be written as a sum of positive squares in 4 ways, for example, as 3976036 + 83905600 = 1994^2 + 9160^2 .

It is not an unprimeable number, because it can be changed into a prime (87881639) 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, 19220 + ... + 23348.

It is an arithmetic number, because the mean of its divisors is an integer number (6808305).

Almost surely, 2^87881636 is an apocalyptic number.

It is an amenable number.

87881636 is a deficient number, since it is larger than the sum of its proper divisors (75517684).

87881636 is a wasteful number, since it uses less digits than its factorization.

87881636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4463 (or 4461 counting only the distinct ones).

The product of its digits is 387072, while the sum is 47.

The square root of 87881636 is about 9374.5205744081. The cubic root of 87881636 is about 444.5965050149.

The spelling of 87881636 in words is "eighty-seven million, eight hundred eighty-one thousand, six hundred thirty-six".