20035640 has 16 divisors (see below), whose sum is σ = 45080280. Its totient is φ = 8014240.

The previous prime is 20035637. The next prime is 20035651. The reversal of 20035640 is 4653002.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 250406 + ... + 250485.

Almost surely, 2^20035640 is an apocalyptic number.

20035640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20035640 is an abundant number, since it is smaller than the sum of its proper divisors (25044640).

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

20035640 is a wasteful number, since it uses less digits than its factorization.

20035640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500902 (or 500898 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 20035640 is about 4476.1188545435. The cubic root of 20035640 is about 271.6029023862.

Adding to 20035640 its reverse (4653002), we get a palindrome (24688642).

The spelling of 20035640 in words is "twenty million, thirty-five thousand, six hundred forty".