1001561161 has 8 divisors (see below), whose sum is σ = 1032290784. Its totient is φ = 971131680.

The previous prime is 1001561153. The next prime is 1001561173. The reversal of 1001561161 is 1611651001.

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

It is a cyclic number.

It is not a de Polignac number, because 1001561161 - 2³ = 1001561153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1001561101) 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, 68251 + ... + 81616.

It is an arithmetic number, because the mean of its divisors is an integer number (129036348).

Almost surely, 2^1001561161 is an apocalyptic number.

It is an amenable number.

1001561161 is a deficient number, since it is larger than the sum of its proper divisors (30729623).

1001561161 is a wasteful number, since it uses less digits than its factorization.

1001561161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150071.

The product of its (nonzero) digits is 180, while the sum is 22.

The square root of 1001561161 is about 31647.4510979952. The cubic root of 1001561161 is about 1000.5201164320.

The spelling of 1001561161 in words is "one billion, one million, five hundred sixty-one thousand, one hundred sixty-one".