2161406520 has 384 divisors, whose sum is σ = 9156551040. Its totient is φ = 429096960.

The previous prime is 2161406519. The next prime is 2161406551. The reversal of 2161406520 is 256041612.

2161406520 is a `hidden beast` number, since 2 + 1 + 6 + 1 + 4 + 0 + 652 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 554980 + ... + 558860.

It is an arithmetic number, because the mean of its divisors is an integer number (23845185).

Almost surely, 2^2161406520 is an apocalyptic number.

2161406520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2161406520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4578275520).

2161406520 is an abundant number, since it is smaller than the sum of its proper divisors (6995144520).

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

2161406520 is a wasteful number, since it uses less digits than its factorization.

2161406520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3935 (or 3928 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 2161406520 is about 46490.9294379022. The cubic root of 2161406520 is about 1292.9413323510.

The spelling of 2161406520 in words is "two billion, one hundred sixty-one million, four hundred six thousand, five hundred twenty".