1640020 has 24 divisors (see below), whose sum is σ = 3525984. Its totient is φ = 640416.

The previous prime is 1640017. The next prime is 1640021. The reversal of 1640020 is 200461.

It is a super-3 number, since 3×1640020³ = 13233316133904024000, which contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94 + ... + 1813.

It is an arithmetic number, because the mean of its divisors is an integer number (146916).

2^1640020 is an apocalyptic number.

1640020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1640020 is an abundant number, since it is smaller than the sum of its proper divisors (1885964).

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

1640020 is a wasteful number, since it uses less digits than its factorization.

1640020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1959 (or 1957 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 1640020 is about 1280.6326561509. The cubic root of 1640020 is about 117.9278501770.

Adding to 1640020 its reverse (200461), we get a palindrome (1840481).

The spelling of 1640020 in words is "one million, six hundred forty thousand, twenty".