87720659513 has 2 divisors, whose sum is σ = 87720659514. Its totient is φ = 87720659512.

The previous prime is 87720659479. The next prime is 87720659627. The reversal of 87720659513 is 31595602778.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73399271929 + 14321387584 = 270923^2 + 119672^2 .

It is a cyclic number.

It is not a de Polignac number, because 87720659513 - 2¹⁰ = 87720658489 is a prime.

It is not a weakly prime, because it can be changed into another prime (87720653513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43860329756 + 43860329757.

It is an arithmetic number, because the mean of its divisors is an integer number (43860329757).

Almost surely, 2^87720659513 is an apocalyptic number.

It is an amenable number.

87720659513 is a deficient number, since it is larger than the sum of its proper divisors (1).

87720659513 is an equidigital number, since it uses as much as digits as its factorization.

87720659513 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3175200, while the sum is 53.

The spelling of 87720659513 in words is "eighty-seven billion, seven hundred twenty million, six hundred fifty-nine thousand, five hundred thirteen".