2161457280 has 96 divisors (see below), whose sum is σ = 7463802060. Its totient is φ = 576387072.

The previous prime is 2161457273. The next prime is 2161457281. The reversal of 2161457280 is 827541612.

2161457280 is a `hidden beast` number, since 2 + 1 + 6 + 1 + 4 + 572 + 80 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 2037980736 + 123476544 = 45144^2 + 11112^2 .

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (2161457281) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 181867 + ... + 193386.

Almost surely, 2^2161457280 is an apocalyptic number.

2161457280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2161457280 is an abundant number, since it is smaller than the sum of its proper divisors (5302344780).

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

2161457280 is a wasteful number, since it uses less digits than its factorization.

2161457280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375278 (or 375263 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 2161457280 is about 46491.4753476377. The cubic root of 2161457280 is about 1292.9514537215.

Adding to 2161457280 its reverse (827541612), we get a palindrome (2988998892).

The spelling of 2161457280 in words is "two billion, one hundred sixty-one million, four hundred fifty-seven thousand, two hundred eighty".