870641434140721 has 2 divisors, whose sum is σ = 870641434140722. Its totient is φ = 870641434140720.

The previous prime is 870641434140623. The next prime is 870641434140769. The reversal of 870641434140721 is 127041434146078.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 543042113053696 + 327599321087025 = 23303264^2 + 18099705^2 .

It is a cyclic number.

It is not a de Polignac number, because 870641434140721 - 2⁷ = 870641434140593 is a prime.

It is a super-2 number, since 2×870641434140721² (a number of 31 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (870641434140791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 435320717070360 + 435320717070361.

It is an arithmetic number, because the mean of its divisors is an integer number (435320717070361).

Almost surely, 2^{870641434140721} is an apocalyptic number.

It is an amenable number.

870641434140721 is a deficient number, since it is larger than the sum of its proper divisors (1).

870641434140721 is an equidigital number, since it uses as much as digits as its factorization.

870641434140721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3612672, while the sum is 52.

Adding to 870641434140721 its reverse (127041434146078), we get a palindrome (997682868286799).

The spelling of 870641434140721 in words is "eight hundred seventy trillion, six hundred forty-one billion, four hundred thirty-four million, one hundred forty thousand, seven hundred twenty-one".