2191493808 has 240 divisors, whose sum is σ = 7375867200. Its totient is φ = 594155520.

The previous prime is 2191493807. The next prime is 2191493861. The reversal of 2191493808 is 8083941912.

It is a super-2 number, since 2×2191493808² = 9605290221004681728, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2191493807) 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, 1782538 + ... + 1783766.

It is an arithmetic number, because the mean of its divisors is an integer number (30732780).

Almost surely, 2^2191493808 is an apocalyptic number.

2191493808 is a gapful number since it is divisible by the number (28) 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 2191493808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3687933600).

2191493808 is an abundant number, since it is smaller than the sum of its proper divisors (5184373392).

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

2191493808 is a wasteful number, since it uses less digits than its factorization.

2191493808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1340 (or 1331 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 45.

The square root of 2191493808 is about 46813.3934681091. The cubic root of 2191493808 is about 1298.9130575252.

The spelling of 2191493808 in words is "two billion, one hundred ninety-one million, four hundred ninety-three thousand, eight hundred eight".