1388434899 has 16 divisors (see below), whose sum is σ = 1951097600. Its totient is φ = 875818656.

The previous prime is 1388434867. The next prime is 1388434909. The reversal of 1388434899 is 9984348831.

It is not a de Polignac number, because 1388434899 - 2⁵ = 1388434867 is a prime.

It is a super-2 number, since 2×1388434899² = 3855502937522280402, which contains 22 as substring.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1388430899) 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, 32562 + ... + 61944.

It is an arithmetic number, because the mean of its divisors is an integer number (121943600).

Almost surely, 2^1388434899 is an apocalyptic number.

1388434899 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1388434899 is a deficient number, since it is larger than the sum of its proper divisors (562662701).

1388434899 is a wasteful number, since it uses less digits than its factorization.

1388434899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30234.

The product of its digits is 5971968, while the sum is 57.

The square root of 1388434899 is about 37261.7082136608. The cubic root of 1388434899 is about 1115.6000039061.

The spelling of 1388434899 in words is "one billion, three hundred eighty-eight million, four hundred thirty-four thousand, eight hundred ninety-nine".