87782521 has 2 divisors, whose sum is σ = 87782522. Its totient is φ = 87782520.

The previous prime is 87782459. The next prime is 87782551. The reversal of 87782521 is 12528778.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 85766121 + 2016400 = 9261^2 + 1420^2 .

It is a cyclic number.

It is not a de Polignac number, because 87782521 - 2¹⁹ = 87258233 is a prime.

It is not a weakly prime, because it can be changed into another prime (87782551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43891260 + 43891261.

It is an arithmetic number, because the mean of its divisors is an integer number (43891261).

Almost surely, 2^87782521 is an apocalyptic number.

It is an amenable number.

87782521 is a deficient number, since it is larger than the sum of its proper divisors (1).

87782521 is an equidigital number, since it uses as much as digits as its factorization.

87782521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 62720, while the sum is 40.

The square root of 87782521 is about 9369.2326793607. The cubic root of 87782521 is about 444.4292999678.

The spelling of 87782521 in words is "eighty-seven million, seven hundred eighty-two thousand, five hundred twenty-one".