2117579940 has 144 divisors (see below), whose sum is σ = 7364203392. Its totient is φ = 482485248.

The previous prime is 2117579929. The next prime is 2117579941. The reversal of 2117579940 is 499757112.

2117579940 is a `hidden beast` number, since 21 + 17 + 579 + 9 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (2117579941) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 422127 + ... + 427113.

Almost surely, 2^2117579940 is an apocalyptic number.

2117579940 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 2117579940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3682101696).

2117579940 is an abundant number, since it is smaller than the sum of its proper divisors (5246623452).

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

2117579940 is a wasteful number, since it uses less digits than its factorization.

2117579940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5346 (or 5341 counting only the distinct ones).

The product of its (nonzero) digits is 158760, while the sum is 45.

The square root of 2117579940 is about 46017.1700564039. The cubic root of 2117579940 is about 1284.1426530882.

The spelling of 2117579940 in words is "two billion, one hundred seventeen million, five hundred seventy-nine thousand, nine hundred forty".