11197561 has 2 divisors, whose sum is σ = 11197562. Its totient is φ = 11197560.

The previous prime is 11197553. The next prime is 11197579. The reversal of 11197561 is 16579111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6656400 + 4541161 = 2580^2 + 2131^2 .

It is an emirp because it is prime and its reverse (16579111) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11197561 - 2³ = 11197553 is a prime.

It is not a weakly prime, because it can be changed into another prime (11197261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5598780 + 5598781.

It is an arithmetic number, because the mean of its divisors is an integer number (5598781).

Almost surely, 2^11197561 is an apocalyptic number.

11197561 is the 1497-th centered decagonal number.

It is an amenable number.

11197561 is a deficient number, since it is larger than the sum of its proper divisors (1).

11197561 is an equidigital number, since it uses as much as digits as its factorization.

11197561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1890, while the sum is 31.

The square root of 11197561 is about 3346.2756909735. The cubic root of 11197561 is about 223.7215462710.

The spelling of 11197561 in words is "eleven million, one hundred ninety-seven thousand, five hundred sixty-one".