2161626240 has 256 divisors, whose sum is σ = 7101354240. Its totient is φ = 559104000.

The previous prime is 2161626239. The next prime is 2161626251. The reversal of 2161626240 is 426261612.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 2161626198 and 2161626207.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13768242 + ... + 13768398.

It is an arithmetic number, because the mean of its divisors is an integer number (27739665).

Almost surely, 2^2161626240 is an apocalyptic number.

2161626240 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 2161626240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3550677120).

2161626240 is an abundant number, since it is smaller than the sum of its proper divisors (4939728000).

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

2161626240 is a wasteful number, since it uses less digits than its factorization.

2161626240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351 (or 339 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 2161626240 is about 46493.2924194448. The cubic root of 2161626240 is about 1292.9851426263.

Adding to 2161626240 its reverse (426261612), we get a palindrome (2587887852).

The spelling of 2161626240 in words is "two billion, one hundred sixty-one million, six hundred twenty-six thousand, two hundred forty".