2061757778 has 4 divisors (see below), whose sum is σ = 3092636670. Its totient is φ = 1030878888.

The previous prime is 2061757777. The next prime is 2061757783. The reversal of 2061757778 is 8777571602.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8777571602 = 2 ⋅4388785801.

It can be written as a sum of positive squares in only one way, i.e., 1996034329 + 65723449 = 44677^2 + 8107^2 .

It is not an unprimeable number, because it can be changed into a prime (2061757777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 515439443 + ... + 515439446.

Almost surely, 2^2061757778 is an apocalyptic number.

2061757778 is a deficient number, since it is larger than the sum of its proper divisors (1030878892).

2061757778 is a wasteful number, since it uses less digits than its factorization.

2061757778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1030878891.

The product of its (nonzero) digits is 1152480, while the sum is 50.

The square root of 2061757778 is about 45406.5829808851. The cubic root of 2061757778 is about 1272.7581319849.

The spelling of 2061757778 in words is "two billion, sixty-one million, seven hundred fifty-seven thousand, seven hundred seventy-eight".