2061617778 has 64 divisors (see below), whose sum is σ = 5291879040. Its totient is φ = 587980800.

The previous prime is 2061617777. The next prime is 2061617783. The reversal of 2061617778 is 8777161602.

2061617778 is a `hidden beast` number, since 20 + 6 + 1 + 617 + 7 + 7 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (2061617777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 91983 + ... + 112178.

It is an arithmetic number, because the mean of its divisors is an integer number (82685610).

Almost surely, 2^2061617778 is an apocalyptic number.

2061617778 is an abundant number, since it is smaller than the sum of its proper divisors (3230261262).

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

2061617778 is a wasteful number, since it uses less digits than its factorization.

2061617778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204200 (or 204194 counting only the distinct ones).

The product of its (nonzero) digits is 197568, while the sum is 45.

The square root of 2061617778 is about 45405.0413280288. The cubic root of 2061617778 is about 1272.7293232060.

It can be divided in two parts, 206 and 1617778, that added together give a square (1617984 = 1272²).

The spelling of 2061617778 in words is "two billion, sixty-one million, six hundred seventeen thousand, seven hundred seventy-eight".