2161062561 has 32 divisors (see below), whose sum is σ = 3362688000. Its totient is φ = 1208952000.

The previous prime is 2161062557. The next prime is 2161062577. The reversal of 2161062561 is 1652601612.

It is not a de Polignac number, because 2161062561 - 2² = 2161062557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2161062521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 307515 + ... + 314463.

It is an arithmetic number, because the mean of its divisors is an integer number (105084000).

Almost surely, 2^2161062561 is an apocalyptic number.

2161062561 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2161062561 is a deficient number, since it is larger than the sum of its proper divisors (1201625439).

2161062561 is a wasteful number, since it uses less digits than its factorization.

2161062561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7269.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 2161062561 is about 46487.2300852610. The cubic root of 2161062561 is about 1292.8727439271.

The spelling of 2161062561 in words is "two billion, one hundred sixty-one million, sixty-two thousand, five hundred sixty-one".