87510855221 has 2 divisors, whose sum is σ = 87510855222. Its totient is φ = 87510855220.

The previous prime is 87510855217. The next prime is 87510855241. The reversal of 87510855221 is 12255801578.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 79911374596 + 7599480625 = 282686^2 + 87175^2 .

It is a cyclic number.

It is not a de Polignac number, because 87510855221 - 2² = 87510855217 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87510855241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43755427610 + 43755427611.

It is an arithmetic number, because the mean of its divisors is an integer number (43755427611).

Almost surely, 2^87510855221 is an apocalyptic number.

It is an amenable number.

87510855221 is a deficient number, since it is larger than the sum of its proper divisors (1).

87510855221 is an equidigital number, since it uses as much as digits as its factorization.

87510855221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 224000, while the sum is 44.

The spelling of 87510855221 in words is "eighty-seven billion, five hundred ten million, eight hundred fifty-five thousand, two hundred twenty-one".