87640622417 has 2 divisors, whose sum is σ = 87640622418. Its totient is φ = 87640622416.

The previous prime is 87640622369. The next prime is 87640622477. The reversal of 87640622417 is 71422604678.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84593140801 + 3047481616 = 290849^2 + 55204^2 .

It is a cyclic number.

It is not a de Polignac number, because 87640622417 - 2⁸ = 87640622161 is a prime.

It is not a weakly prime, because it can be changed into another prime (87640622477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43820311208 + 43820311209.

It is an arithmetic number, because the mean of its divisors is an integer number (43820311209).

Almost surely, 2^87640622417 is an apocalyptic number.

It is an amenable number.

87640622417 is a deficient number, since it is larger than the sum of its proper divisors (1).

87640622417 is an equidigital number, since it uses as much as digits as its factorization.

87640622417 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 903168, while the sum is 47.

The spelling of 87640622417 in words is "eighty-seven billion, six hundred forty million, six hundred twenty-two thousand, four hundred seventeen".