1388283981 has 16 divisors (see below), whose sum is σ = 2116105344. Its totient is φ = 793070784.

The previous prime is 1388283973. The next prime is 1388284031. The reversal of 1388283981 is 1893828831.

1388283981 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1388283981 - 2³ = 1388283973 is a prime.

It is a super-2 number, since 2×1388283981² = 3854664823802416722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1388283901) 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, 83911 + ... + 99083.

It is an arithmetic number, because the mean of its divisors is an integer number (132256584).

Almost surely, 2^1388283981 is an apocalyptic number.

It is an amenable number.

1388283981 is a deficient number, since it is larger than the sum of its proper divisors (727821363).

1388283981 is a wasteful number, since it uses less digits than its factorization.

1388283981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19540.

The product of its digits is 663552, while the sum is 51.

The square root of 1388283981 is about 37259.6830501817. The cubic root of 1388283981 is about 1115.5595818399.

The spelling of 1388283981 in words is "one billion, three hundred eighty-eight million, two hundred eighty-three thousand, nine hundred eighty-one".