387740557 has 2 divisors, whose sum is σ = 387740558. Its totient is φ = 387740556.

The previous prime is 387740489. The next prime is 387740569. The reversal of 387740557 is 755047783.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 205463556 + 182277001 = 14334^2 + 13501^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-387740557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (387740597) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 193870278 + 193870279.

It is an arithmetic number, because the mean of its divisors is an integer number (193870279).

Almost surely, 2^387740557 is an apocalyptic number.

It is an amenable number.

387740557 is a deficient number, since it is larger than the sum of its proper divisors (1).

387740557 is an equidigital number, since it uses as much as digits as its factorization.

387740557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 823200, while the sum is 46.

The square root of 387740557 is about 19691.1288909499. The cubic root of 387740557 is about 729.2006995439.

The spelling of 387740557 in words is "three hundred eighty-seven million, seven hundred forty thousand, five hundred fifty-seven".