2181561460 has 48 divisors (see below), whose sum is σ = 4938183936. Its totient is φ = 804765312.

The previous prime is 2181561457. The next prime is 2181561463. The reversal of 2181561460 is 641651812.

It is an interprime number because it is at equal distance from previous prime (2181561457) and next prime (2181561463).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2181561463) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 341859 + ... + 348181.

It is an arithmetic number, because the mean of its divisors is an integer number (102878832).

Almost surely, 2^2181561460 is an apocalyptic number.

2181561460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2181561460 is an abundant number, since it is smaller than the sum of its proper divisors (2756622476).

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

2181561460 is a wasteful number, since it uses less digits than its factorization.

2181561460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7672 (or 7670 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 34.

The square root of 2181561460 is about 46707.1885259646. The cubic root of 2181561460 is about 1296.9477624129.

The spelling of 2181561460 in words is "two billion, one hundred eighty-one million, five hundred sixty-one thousand, four hundred sixty".