87204521 has 2 divisors, whose sum is σ = 87204522. Its totient is φ = 87204520.

The previous prime is 87204517. The next prime is 87204527. The reversal of 87204521 is 12540278.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62094400 + 25110121 = 7880^2 + 5011^2 .

It is a cyclic number.

It is not a de Polignac number, because 87204521 - 2² = 87204517 is a prime.

It is not a weakly prime, because it can be changed into another prime (87204527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43602260 + 43602261.

It is an arithmetic number, because the mean of its divisors is an integer number (43602261).

Almost surely, 2^87204521 is an apocalyptic number.

It is an amenable number.

87204521 is a deficient number, since it is larger than the sum of its proper divisors (1).

87204521 is an equidigital number, since it uses as much as digits as its factorization.

87204521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4480, while the sum is 29.

The square root of 87204521 is about 9338.3360937589. The cubic root of 87204521 is about 443.4517097097.

Adding to 87204521 its reverse (12540278), we get a palindrome (99744799).

The spelling of 87204521 in words is "eighty-seven million, two hundred four thousand, five hundred twenty-one".