2161021570 has 16 divisors (see below), whose sum is σ = 3890368440. Its totient is φ = 864290944.

The previous prime is 2161021547. The next prime is 2161021571. The reversal of 2161021570 is 751201612.

It can be written as a sum of positive squares in 4 ways, for example, as 1576010601 + 585010969 = 39699^2 + 24187^2 .

It is not an unprimeable number, because it can be changed into a prime (2161021571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 133896 + ... + 149164.

Almost surely, 2^2161021570 is an apocalyptic number.

2161021570 is a deficient number, since it is larger than the sum of its proper divisors (1729346870).

2161021570 is a wasteful number, since it uses less digits than its factorization.

2161021570 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29429.

The product of its (nonzero) digits is 840, while the sum is 25.

The square root of 2161021570 is about 46486.7891986530. The cubic root of 2161021570 is about 1292.8645694789.

The spelling of 2161021570 in words is "two billion, one hundred sixty-one million, twenty-one thousand, five hundred seventy".