1099207561761 has 9 divisors (see below), whose sum is σ = 1587748799091. Its totient is φ = 732802944312.

The previous prime is 1099207561747. The next prime is 1099207561787. The reversal of 1099207561761 is 1671657029901.

The square root of 1099207561761 is 1048431.

It is a perfect power (a square), and thus also a powerful number.

1099207561761 is a `hidden beast` number, since 1 + 0 + 9 + 9 + 2 + 0 + 7 + 561 + 76 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1096743035025 + 2464526736 = 1047255^2 + 49644^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 1099207561761 - 2⁷ = 1099207561633 is a prime.

It is a super-2 number, since 2×1099207561761² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1099207561698 and 1099207561707.

It is not an unprimeable number, because it can be changed into a prime (1099207561061) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2970555 + ... + 3320031.

Almost surely, 2^{1099207561761} is an apocalyptic number.

1099207561761 is the 1048431-st square number.

1099207561761 is the 524216-th centered octagonal number.

It is an amenable number.

1099207561761 is a deficient number, since it is larger than the sum of its proper divisors (488541237330).

1099207561761 is an frugal number, since it uses more digits than its factorization.

1099207561761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 698960 (or 349480 counting only the distinct ones).

The product of its (nonzero) digits is 1428840, while the sum is 54.

The spelling of 1099207561761 in words is "one trillion, ninety-nine billion, two hundred seven million, five hundred sixty-one thousand, seven hundred sixty-one".