1087561 has 2 divisors, whose sum is σ = 1087562. Its totient is φ = 1087560.

The previous prime is 1087553. The next prime is 1087589. The reversal of 1087561 is 1657801.

It is a happy number.

It is an a-pointer prime, because the next prime (1087589) can be obtained adding 1087561 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 640000 + 447561 = 800^2 + 669^2 .

It is an emirp because it is prime and its reverse (1657801) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1087561 - 2³ = 1087553 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1087591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 543780 + 543781.

It is an arithmetic number, because the mean of its divisors is an integer number (543781).

2^1087561 is an apocalyptic number.

It is an amenable number.

1087561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1087561 is an equidigital number, since it uses as much as digits as its factorization.

1087561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1680, while the sum is 28.

The square root of 1087561 is about 1042.8619275820. The cubic root of 1087561 is about 102.8374285225.

It can be divided in two parts, 10 and 87561, that added together give a triangular number (87571 = T₄₁₈).

The spelling of 1087561 in words is "one million, eighty-seven thousand, five hundred sixty-one".