2161263520 has 48 divisors (see below), whose sum is σ = 5498758440. Its totient is φ = 798004224.

The previous prime is 2161263491. The next prime is 2161263527. The reversal of 2161263520 is 253621612.

It can be written as a sum of positive squares in 4 ways, for example, as 746600976 + 1414662544 = 27324^2 + 37612^2 .

It is not an unprimeable number, because it can be changed into a prime (2161263527) 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, 517455 + ... + 521614.

Almost surely, 2^2161263520 is an apocalyptic number.

2161263520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2161263520 is an abundant number, since it is smaller than the sum of its proper divisors (3337494920).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2161263520 is a wasteful number, since it uses less digits than its factorization.

2161263520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1039097 (or 1039089 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 2161263520 is about 46489.3914780566. The cubic root of 2161263520 is about 1292.9128177879.

The spelling of 2161263520 in words is "two billion, one hundred sixty-one million, two hundred sixty-three thousand, five hundred twenty".