1381652640 has 480 divisors, whose sum is σ = 5327562240. Its totient is φ = 335923200.

The previous prime is 1381652639. The next prime is 1381652647. The reversal of 1381652640 is 462561831.

It is a happy number.

1381652640 is a `hidden beast` number, since 1 + 3 + 8 + 1 + 6 + 5 + 2 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1381652595 and 1381652604.

It is not an unprimeable number, because it can be changed into a prime (1381652647) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 7633350 + ... + 7633530.

It is an arithmetic number, because the mean of its divisors is an integer number (11099088).

Almost surely, 2^1381652640 is an apocalyptic number.

1381652640 is a gapful number since it is divisible by the number (10) 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 1381652640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2663781120).

1381652640 is an abundant number, since it is smaller than the sum of its proper divisors (3945909600).

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

1381652640 is a wasteful number, since it uses less digits than its factorization.

1381652640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258 (or 241 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 1381652640 is about 37170.5883730672. The cubic root of 1381652640 is about 1113.7805351626.

The spelling of 1381652640 in words is "one billion, three hundred eighty-one million, six hundred fifty-two thousand, six hundred forty".