1097966569921 has 9 divisors (see below), whose sum is σ = 1188937130979. Its totient is φ = 1013495028936.

The previous prime is 1097966569897. The next prime is 1097966569927. The reversal of 1097966569921 is 1299656697901.

The square root of 1097966569921 is 1047839.

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

It can be written as a sum of positive squares in only one way, i.e., 162421090225 + 935545479696 = 403015^2 + 967236^2 .

It is not a de Polignac number, because 1097966569921 - 2³³ = 1089376635329 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1097966569927) 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, 13581606 + ... + 13662208.

Almost surely, 2^{1097966569921} is an apocalyptic number.

1097966569921 is the 1047839-th square number.

1097966569921 is the 523920-th centered octagonal number.

It is an amenable number.

1097966569921 is a deficient number, since it is larger than the sum of its proper divisors (90970561058).

1097966569921 is an frugal number, since it uses more digits than its factorization.

1097966569921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161232 (or 80616 counting only the distinct ones).

The product of its (nonzero) digits is 99202320, while the sum is 70.

The spelling of 1097966569921 in words is "one trillion, ninety-seven billion, nine hundred sixty-six million, five hundred sixty-nine thousand, nine hundred twenty-one".