1388995812 has 36 divisors (see below), whose sum is σ = 3717608076. Its totient is φ = 435763200.

The previous prime is 1388995807. The next prime is 1388995823. The reversal of 1388995812 is 2185998831.

It can be written as a sum of positive squares in 2 ways, for example, as 415181376 + 973814436 = 20376^2 + 31206^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1134189 + ... + 1135412.

It is an arithmetic number, because the mean of its divisors is an integer number (103266891).

Almost surely, 2^1388995812 is an apocalyptic number.

1388995812 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1388995812 is an abundant number, since it is smaller than the sum of its proper divisors (2328612264).

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

1388995812 is a wasteful number, since it uses less digits than its factorization.

1388995812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2269628 (or 2269623 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 54.

The square root of 1388995812 is about 37269.2341214573. The cubic root of 1388995812 is about 1115.7502138771.

The spelling of 1388995812 in words is "one billion, three hundred eighty-eight million, nine hundred ninety-five thousand, eight hundred twelve".