2421640 has 32 divisors (see below), whose sum is σ = 5869080. Its totient is φ = 893952.

The previous prime is 2421593. The next prime is 2421641. The reversal of 2421640 is 461242.

It can be written as a sum of positive squares in 4 ways, for example, as 996004 + 1425636 = 998^2 + 1194^2 .

It is not an unprimeable number, because it can be changed into a prime (2421641) 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, 1809 + ... + 2848.

2^2421640 is an apocalyptic number.

2421640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2421640 is an abundant number, since it is smaller than the sum of its proper divisors (3447440).

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

2421640 is a wasteful number, since it uses less digits than its factorization.

2421640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4681 (or 4677 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 2421640 is about 1556.1619453000. The cubic root of 2421640 is about 134.2877901768.

Adding to 2421640 its reverse (461242), we get a palindrome (2882882).

The spelling of 2421640 in words is "two million, four hundred twenty-one thousand, six hundred forty".