1388981958 has 128 divisors (see below), whose sum is σ = 3554783232. Its totient is φ = 352066176.

The previous prime is 1388981933. The next prime is 1388981977. The reversal of 1388981958 is 8591898831.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1572585 + ... + 1573467.

It is an arithmetic number, because the mean of its divisors is an integer number (27771744).

Almost surely, 2^1388981958 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1388981958, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1777391616).

1388981958 is an abundant number, since it is smaller than the sum of its proper divisors (2165801274).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1388981958 is a wasteful number, since it uses less digits than its factorization.

1388981958 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018.

The product of its digits is 4976640, while the sum is 60.

The square root of 1388981958 is about 37269.0482572335. The cubic root of 1388981958 is about 1115.7465043255.

The spelling of 1388981958 in words is "one billion, three hundred eighty-eight million, nine hundred eighty-one thousand, nine hundred fifty-eight".