87847813 has 2 divisors, whose sum is σ = 87847814. Its totient is φ = 87847812.

The previous prime is 87847783. The next prime is 87847819. The reversal of 87847813 is 31874878.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73582084 + 14265729 = 8578^2 + 3777^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-87847813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87847819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43923906 + 43923907.

It is an arithmetic number, because the mean of its divisors is an integer number (43923907).

Almost surely, 2^87847813 is an apocalyptic number.

It is an amenable number.

87847813 is a deficient number, since it is larger than the sum of its proper divisors (1).

87847813 is an equidigital number, since it uses as much as digits as its factorization.

87847813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 301056, while the sum is 46.

The square root of 87847813 is about 9372.7164152128. The cubic root of 87847813 is about 444.5394604193.

The spelling of 87847813 in words is "eighty-seven million, eight hundred forty-seven thousand, eight hundred thirteen".