1906778220 has 48 divisors (see below), whose sum is σ = 5340991488. Its totient is φ = 508282560.

The previous prime is 1906778161. The next prime is 1906778221. The reversal of 1906778220 is 228776091.

It is not an unprimeable number, because it can be changed into a prime (1906778221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 234015 + ... + 242025.

It is an arithmetic number, because the mean of its divisors is an integer number (111270656).

Almost surely, 2^1906778220 is an apocalyptic number.

1906778220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1906778220 is an abundant number, since it is smaller than the sum of its proper divisors (3434213268).

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

1906778220 is a wasteful number, since it uses less digits than its factorization.

1906778220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11990 (or 11988 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 42.

The square root of 1906778220 is about 43666.6717302796. The cubic root of 1906778220 is about 1240.0334321545.

The spelling of 1906778220 in words is "one billion, nine hundred six million, seven hundred seventy-eight thousand, two hundred twenty".