1388188857 has 16 divisors (see below), whose sum is σ = 2019886848. Its totient is φ = 841033680.

The previous prime is 1388188847. The next prime is 1388188859. The reversal of 1388188857 is 7588818831.

It is not a de Polignac number, because 1388188857 - 2⁷ = 1388188729 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1388188797 and 1388188806.

It is not an unprimeable number, because it can be changed into a prime (1388188859) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 124098 + ... + 134820.

It is an arithmetic number, because the mean of its divisors is an integer number (126242928).

Almost surely, 2^1388188857 is an apocalyptic number.

It is an amenable number.

1388188857 is a deficient number, since it is larger than the sum of its proper divisors (631697991).

1388188857 is a wasteful number, since it uses less digits than its factorization.

1388188857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14660.

The product of its digits is 3440640, while the sum is 57.

The square root of 1388188857 is about 37258.4065279233. The cubic root of 1388188857 is about 1115.5341022035.

The spelling of 1388188857 in words is "one billion, three hundred eighty-eight million, one hundred eighty-eight thousand, eight hundred fifty-seven".