1001387520 has 360 divisors, whose sum is σ = 4038853104. Its totient is φ = 228630528.

The previous prime is 1001387509. The next prime is 1001387531. The reversal of 1001387520 is 257831001.

1001387520 is a `hidden beast` number, since 1 + 0 + 0 + 138 + 7 + 520 = 666.

It is an interprime number because it is at equal distance from previous prime (1001387509) and next prime (1001387531).

It is a tau number, because it is divible by the number of its divisors (360).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1128517 + ... + 1129403.

Almost surely, 2^1001387520 is an apocalyptic number.

1001387520 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 1001387520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2019426552).

1001387520 is an abundant number, since it is smaller than the sum of its proper divisors (3037465584).

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

1001387520 is an equidigital number, since it uses as much as digits as its factorization.

1001387520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 930 (or 904 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 27.

The square root of 1001387520 is about 31644.7076143863. The cubic root of 1001387520 is about 1000.4622929190.

It can be divided in two parts, 1001 and 387520, that added together give a triangular number (388521 = T₈₈₁).

The spelling of 1001387520 in words is "one billion, one million, three hundred eighty-seven thousand, five hundred twenty".