3788778835661 has 2 divisors, whose sum is σ = 3788778835662. Its totient is φ = 3788778835660.

The previous prime is 3788778835651. The next prime is 3788778835697. The reversal of 3788778835661 is 1665388778873.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3331741993636 + 457036842025 = 1825306^2 + 676045^2 .

It is a cyclic number.

It is not a de Polignac number, because 3788778835661 - 2²⁶ = 3788711726797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3788778835601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1894389417830 + 1894389417831.

It is an arithmetic number, because the mean of its divisors is an integer number (1894389417831).

Almost surely, 2^{3788778835661} is an apocalyptic number.

It is an amenable number.

3788778835661 is a deficient number, since it is larger than the sum of its proper divisors (1).

3788778835661 is an equidigital number, since it uses as much as digits as its factorization.

3788778835661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2275983360, while the sum is 77.

The spelling of 3788778835661 in words is "three trillion, seven hundred eighty-eight billion, seven hundred seventy-eight million, eight hundred thirty-five thousand, six hundred sixty-one".