1387220736 has 144 divisors (see below), whose sum is σ = 4158379008. Its totient is φ = 406732800.

The previous prime is 1387220717. The next prime is 1387220753. The reversal of 1387220736 is 6370227831.

It is a junction number, because it is equal to n+sod(n) for n = 1387220694 and 1387220703.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 259240 + ... + 264536.

It is an arithmetic number, because the mean of its divisors is an integer number (28877632).

Almost surely, 2^1387220736 is an apocalyptic number.

1387220736 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1387220736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2079189504).

1387220736 is an abundant number, since it is smaller than the sum of its proper divisors (2771158272).

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

1387220736 is a wasteful number, since it uses less digits than its factorization.

1387220736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5358 (or 5344 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 39.

The square root of 1387220736 is about 37245.4122812461. The cubic root of 1387220736 is about 1115.2747179130.

The spelling of 1387220736 in words is "one billion, three hundred eighty-seven million, two hundred twenty thousand, seven hundred thirty-six".