1387205808 has 160 divisors (see below), whose sum is σ = 4034741760. Its totient is φ = 408545280.

The previous prime is 1387205803. The next prime is 1387205839. The reversal of 1387205808 is 8085027831.

It is a happy number.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 1387205808.

It is not an unprimeable number, because it can be changed into a prime (1387205801) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 859210 + ... + 860822.

It is an arithmetic number, because the mean of its divisors is an integer number (25217136).

Almost surely, 2^1387205808 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1387205808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2017370880).

1387205808 is an abundant number, since it is smaller than the sum of its proper divisors (2647535952).

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

1387205808 is a wasteful number, since it uses less digits than its factorization.

1387205808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1707 (or 1701 counting only the distinct ones).

The product of its (nonzero) digits is 107520, while the sum is 42.

The square root of 1387205808 is about 37245.2118801867. The cubic root of 1387205808 is about 1115.2707173768.

It can be divided in two parts, 13 and 87205808, that added together give a triangular number (87205821 = T₁₃₂₀₆).

The spelling of 1387205808 in words is "one billion, three hundred eighty-seven million, two hundred five thousand, eight hundred eight".