1087780861 has 2 divisors, whose sum is σ = 1087780862. Its totient is φ = 1087780860.

The previous prime is 1087780849. The next prime is 1087780867. The reversal of 1087780861 is 1680877801.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 600740100 + 487040761 = 24510^2 + 22069^2 .

It is a cyclic number.

It is not a de Polignac number, because 1087780861 - 2⁹ = 1087780349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1087780867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 543890430 + 543890431.

It is an arithmetic number, because the mean of its divisors is an integer number (543890431).

Almost surely, 2^1087780861 is an apocalyptic number.

It is an amenable number.

1087780861 is a deficient number, since it is larger than the sum of its proper divisors (1).

1087780861 is an equidigital number, since it uses as much as digits as its factorization.

1087780861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 150528, while the sum is 46.

The square root of 1087780861 is about 32981.5230242631. The cubic root of 1087780861 is about 1028.4435791664.

The spelling of 1087780861 in words is "one billion, eighty-seven million, seven hundred eighty thousand, eight hundred sixty-one".