1097561 has 4 divisors (see below), whose sum is σ = 1101072. Its totient is φ = 1094052.

The previous prime is 1097557. The next prime is 1097599. The reversal of 1097561 is 1657901.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1097561 - 2² = 1097557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1097501) 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, 1235 + ... + 1928.

It is an arithmetic number, because the mean of its divisors is an integer number (275268).

2^1097561 is an apocalyptic number.

It is an amenable number.

1097561 is a deficient number, since it is larger than the sum of its proper divisors (3511).

1097561 is an equidigital number, since it uses as much as digits as its factorization.

1097561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3510.

The product of its (nonzero) digits is 1890, while the sum is 29.

The square root of 1097561 is about 1047.6454552949. The cubic root of 1097561 is about 103.1516602023.

The spelling of 1097561 in words is "one million, ninety-seven thousand, five hundred sixty-one".