2215917864 has 128 divisors (see below), whose sum is σ = 6654864000. Its totient is φ = 680804352.

The previous prime is 2215917833. The next prime is 2215917877. The reversal of 2215917864 is 4687195122.

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, 144552 + ... + 159144.

It is an arithmetic number, because the mean of its divisors is an integer number (51991125).

Almost surely, 2^2215917864 is an apocalyptic number.

2215917864 is a gapful number since it is divisible by the number (24) 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 2215917864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3327432000).

2215917864 is an abundant number, since it is smaller than the sum of its proper divisors (4438946136).

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

2215917864 is a wasteful number, since it uses less digits than its factorization.

2215917864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14664 (or 14654 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 2215917864 is about 47073.5367696119. The cubic root of 2215917864 is about 1303.7206751756.

The spelling of 2215917864 in words is "two billion, two hundred fifteen million, nine hundred seventeen thousand, eight hundred sixty-four".