1151123561 has 4 divisors (see below), whose sum is σ = 1315569792. Its totient is φ = 986677332.

The previous prime is 1151123551. The next prime is 1151123579. The reversal of 1151123561 is 1653211511.

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 1151123561 - 2²² = 1146929257 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1151123561.

It is not an unprimeable number, because it can be changed into a prime (1151123521) 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, 82223105 + ... + 82223118.

It is an arithmetic number, because the mean of its divisors is an integer number (328892448).

Almost surely, 2^1151123561 is an apocalyptic number.

It is an amenable number.

1151123561 is a deficient number, since it is larger than the sum of its proper divisors (164446231).

1151123561 is an equidigital number, since it uses as much as digits as its factorization.

1151123561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164446230.

The product of its digits is 900, while the sum is 26.

The square root of 1151123561 is about 33928.2118744858. The cubic root of 1151123561 is about 1048.0306430180.

The spelling of 1151123561 in words is "one billion, one hundred fifty-one million, one hundred twenty-three thousand, five hundred sixty-one".