20341640 has 64 divisors (see below), whose sum is σ = 50621760. Its totient is φ = 7294720.

The previous prime is 20341627. The next prime is 20341649. The reversal of 20341640 is 4614302.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (20341649) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 36242 + ... + 36798.

It is an arithmetic number, because the mean of its divisors is an integer number (790965).

Almost surely, 2^20341640 is an apocalyptic number.

20341640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20341640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25310880).

20341640 is an abundant number, since it is smaller than the sum of its proper divisors (30280120).

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

20341640 is a wasteful number, since it uses less digits than its factorization.

20341640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 662 (or 658 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 20341640 is about 4510.1707284758. The cubic root of 20341640 is about 272.9786330426.

Adding to 20341640 its reverse (4614302), we get a palindrome (24955942).

The spelling of 20341640 in words is "twenty million, three hundred forty-one thousand, six hundred forty".