1001189561 has 8 divisors (see below), whose sum is σ = 1018303104. Its totient is φ = 984218400.

The previous prime is 1001189513. The next prime is 1001189573. The reversal of 1001189561 is 1659811001.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1001189561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1001180561) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21365 + ... + 49586.

It is an arithmetic number, because the mean of its divisors is an integer number (127287888).

Almost surely, 2^1001189561 is an apocalyptic number.

It is an amenable number.

1001189561 is a deficient number, since it is larger than the sum of its proper divisors (17113543).

1001189561 is a wasteful number, since it uses less digits than its factorization.

1001189561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71191.

The product of its (nonzero) digits is 2160, while the sum is 32.

The square root of 1001189561 is about 31641.5796223893. The cubic root of 1001189561 is about 1000.3963632088.

The spelling of 1001189561 in words is "one billion, one million, one hundred eighty-nine thousand, five hundred sixty-one".