87438521 has 2 divisors, whose sum is σ = 87438522. Its totient is φ = 87438520.

The previous prime is 87438503. The next prime is 87438529. The reversal of 87438521 is 12583478.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71149225 + 16289296 = 8435^2 + 4036^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-87438521 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (87438529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43719260 + 43719261.

It is an arithmetic number, because the mean of its divisors is an integer number (43719261).

Almost surely, 2^87438521 is an apocalyptic number.

It is an amenable number.

87438521 is a deficient number, since it is larger than the sum of its proper divisors (1).

87438521 is an equidigital number, since it uses as much as digits as its factorization.

87438521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 38.

The square root of 87438521 is about 9350.8566987202. The cubic root of 87438521 is about 443.8480004145.

The spelling of 87438521 in words is "eighty-seven million, four hundred thirty-eight thousand, five hundred twenty-one".