387779389 has 2 divisors, whose sum is σ = 387779390. Its totient is φ = 387779388.

The previous prime is 387779309. The next prime is 387779393. The reversal of 387779389 is 983977783.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 386908900 + 870489 = 19670^2 + 933^2 .

It is an emirp because it is prime and its reverse (983977783) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-387779389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (387779309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 193889694 + 193889695.

It is an arithmetic number, because the mean of its divisors is an integer number (193889695).

Almost surely, 2^387779389 is an apocalyptic number.

It is an amenable number.

387779389 is a deficient number, since it is larger than the sum of its proper divisors (1).

387779389 is an equidigital number, since it uses as much as digits as its factorization.

387779389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16003008, while the sum is 61.

The square root of 387779389 is about 19692.1148940382. The cubic root of 387779389 is about 729.2250417454.

The spelling of 387779389 in words is "three hundred eighty-seven million, seven hundred seventy-nine thousand, three hundred eighty-nine".