1388389478 has 32 divisors (see below), whose sum is σ = 2441940480. Its totient is φ = 579608640.

The previous prime is 1388389417. The next prime is 1388389487. The reversal of 1388389478 is 8749838831.

It is a super-2 number, since 2×1388389478² = 3855250685242224968, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 470933 + ... + 473871.

It is an arithmetic number, because the mean of its divisors is an integer number (76310640).

Almost surely, 2^1388389478 is an apocalyptic number.

1388389478 is a deficient number, since it is larger than the sum of its proper divisors (1053551002).

1388389478 is a wasteful number, since it uses less digits than its factorization.

1388389478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3812.

The product of its digits is 9289728, while the sum is 59.

The square root of 1388389478 is about 37261.0987223941. The cubic root of 1388389478 is about 1115.5878385967.

The spelling of 1388389478 in words is "one billion, three hundred eighty-eight million, three hundred eighty-nine thousand, four hundred seventy-eight".