87443656261021 has 2 divisors, whose sum is σ = 87443656261022. Its totient is φ = 87443656261020.

The previous prime is 87443656261019. The next prime is 87443656261057. The reversal of 87443656261021 is 12016265634478.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62370743175225 + 25072913085796 = 7897515^2 + 5007286^2 .

It is a cyclic number.

It is not a de Polignac number, because 87443656261021 - 2¹ = 87443656261019 is a prime.

Together with 87443656261019, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87443656261001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43721828130510 + 43721828130511.

It is an arithmetic number, because the mean of its divisors is an integer number (43721828130511).

Almost surely, 2^{87443656261021} is an apocalyptic number.

It is an amenable number.

87443656261021 is a deficient number, since it is larger than the sum of its proper divisors (1).

87443656261021 is an equidigital number, since it uses as much as digits as its factorization.

87443656261021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11612160, while the sum is 55.

The spelling of 87443656261021 in words is "eighty-seven trillion, four hundred forty-three billion, six hundred fifty-six million, two hundred sixty-one thousand, twenty-one".