1089729661 has 16 divisors (see below), whose sum is σ = 1144548144. Its totient is φ = 1036399104.

The previous prime is 1089729653. The next prime is 1089729671. The reversal of 1089729661 is 1669279801.

It can be written as a sum of positive squares in 8 ways, for example, as 61308900 + 1028420761 = 7830^2 + 32069^2 .

It is a cyclic number.

It is not a de Polignac number, because 1089729661 - 2³ = 1089729653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1089729671) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 620761 + ... + 622513.

It is an arithmetic number, because the mean of its divisors is an integer number (71534259).

Almost surely, 2^1089729661 is an apocalyptic number.

It is an amenable number.

1089729661 is a deficient number, since it is larger than the sum of its proper divisors (54818483).

1089729661 is a wasteful number, since it uses less digits than its factorization.

1089729661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2160.

The product of its (nonzero) digits is 326592, while the sum is 49.

The square root of 1089729661 is about 33011.0536184473. The cubic root of 1089729661 is about 1029.0573777797.

The spelling of 1089729661 in words is "one billion, eighty-nine million, seven hundred twenty-nine thousand, six hundred sixty-one".