1090556861 has 4 divisors (see below), whose sum is σ = 1128162300. Its totient is φ = 1052951424.

The previous prime is 1090556849. The next prime is 1090556867. The reversal of 1090556861 is 1686550901.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 553707961 + 536848900 = 23531^2 + 23170^2 .

It is a cyclic number.

It is not a de Polignac number, because 1090556861 - 2¹⁸ = 1090294717 is a prime.

It is a super-3 number, since 3×1090556861³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1090556867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18802676 + ... + 18802733.

It is an arithmetic number, because the mean of its divisors is an integer number (282040575).

Almost surely, 2^1090556861 is an apocalyptic number.

It is an amenable number.

1090556861 is a deficient number, since it is larger than the sum of its proper divisors (37605439).

1090556861 is an equidigital number, since it uses as much as digits as its factorization.

1090556861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37605438.

The product of its (nonzero) digits is 64800, while the sum is 41.

The square root of 1090556861 is about 33023.5803782691. The cubic root of 1090556861 is about 1029.3176934024.

The spelling of 1090556861 in words is "one billion, ninety million, five hundred fifty-six thousand, eight hundred sixty-one".