2815661900 has 72 divisors (see below), whose sum is σ = 6273723456. Its totient is φ = 1096345600.

The previous prime is 2815661899. The next prime is 2815661911. The reversal of 2815661900 is 91665182.

It is a super-2 number, since 2×2815661900² = 15855903870223220000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 924380 + ... + 927420.

It is an arithmetic number, because the mean of its divisors is an integer number (87135048).

Almost surely, 2^2815661900 is an apocalyptic number.

2815661900 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 2815661900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3136861728).

2815661900 is an abundant number, since it is smaller than the sum of its proper divisors (3458061556).

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

2815661900 is a wasteful number, since it uses less digits than its factorization.

2815661900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3299 (or 3292 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 2815661900 is about 53062.8108942600. The cubic root of 2815661900 is about 1412.0828162069.

The spelling of 2815661900 in words is "two billion, eight hundred fifteen million, six hundred sixty-one thousand, nine hundred".