1087781 has 2 divisors, whose sum is σ = 1087782. Its totient is φ = 1087780.

The previous prime is 1087753. The next prime is 1087787. The reversal of 1087781 is 1877801.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 919681 + 168100 = 959^2 + 410^2 .

It is an emirp because it is prime and its reverse (1877801) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1087781 - 2⁶ = 1087717 is a prime.

It is a super-2 number, since 2×1087781² = 2366535007922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1087787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 543890 + 543891.

It is an arithmetic number, because the mean of its divisors is an integer number (543891).

2^1087781 is an apocalyptic number.

It is an amenable number.

1087781 is a deficient number, since it is larger than the sum of its proper divisors (1).

1087781 is an equidigital number, since it uses as much as digits as its factorization.

1087781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3136, while the sum is 32.

The square root of 1087781 is about 1042.9674012164. The cubic root of 1087781 is about 102.8443622972.

The spelling of 1087781 in words is "one million, eighty-seven thousand, seven hundred eighty-one".