1640636120 has 16 divisors (see below), whose sum is σ = 3691431360. Its totient is φ = 656254432.

The previous prime is 1640636099. The next prime is 1640636143. The reversal of 1640636120 is 216360461.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20507912 + ... + 20507991.

It is an arithmetic number, because the mean of its divisors is an integer number (230714460).

Almost surely, 2^1640636120 is an apocalyptic number.

1640636120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1640636120 is an abundant number, since it is smaller than the sum of its proper divisors (2050795240).

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

1640636120 is a wasteful number, since it uses less digits than its factorization.

1640636120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41015914 (or 41015910 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 1640636120 is about 40504.7666330767. The cubic root of 1640636120 is about 1179.4261597465.

Adding to 1640636120 its reverse (216360461), we get a palindrome (1856996581).

The spelling of 1640636120 in words is "one billion, six hundred forty million, six hundred thirty-six thousand, one hundred twenty".