2001640525 has 6 divisors (see below), whose sum is σ = 2482034282. Its totient is φ = 1601312400.

The previous prime is 2001640517. The next prime is 2001640601. The reversal of 2001640525 is 5250461002.

It can be written as a sum of positive squares in 3 ways, for example, as 1225449 + 2000415076 = 1107^2 + 44726^2 .

It is not a de Polignac number, because 2001640525 - 2³ = 2001640517 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25), and also a Moran number because the ratio is a prime number: 80065621 = 2001640525 / (2 + 0 + 0 + 1 + 6 + 4 + 0 + 5 + 2 + 5).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2001640525.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 40032786 + ... + 40032835.

Almost surely, 2^2001640525 is an apocalyptic number.

2001640525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2001640525 is a deficient number, since it is larger than the sum of its proper divisors (480393757).

2001640525 is an equidigital number, since it uses as much as digits as its factorization.

2001640525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80065631 (or 80065626 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 2001640525 is about 44739.6974173943. The cubic root of 2001640525 is about 1260.2654444108.

The spelling of 2001640525 in words is "two billion, one million, six hundred forty thousand, five hundred twenty-five".