2191078890 has 512 divisors, whose sum is σ = 8027873280. Its totient is φ = 413994240.

The previous prime is 2191078873. The next prime is 2191078891. The reversal of 2191078890 is 988701912.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191078891) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 32702637 + ... + 32702703.

It is an arithmetic number, because the mean of its divisors is an integer number (15679440).

Almost surely, 2^2191078890 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2191078890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4013936640).

2191078890 is an abundant number, since it is smaller than the sum of its proper divisors (5836794390).

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

2191078890 is a wasteful number, since it uses less digits than its factorization.

2191078890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136 (or 108 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 45.

The square root of 2191078890 is about 46808.9616419762. The cubic root of 2191078890 is about 1298.8310774587.

The spelling of 2191078890 in words is "two billion, one hundred ninety-one million, seventy-eight thousand, eight hundred ninety".