20343621 has 16 divisors (see below), whose sum is σ = 27869184. Its totient is φ = 13193904.

The previous prime is 20343619. The next prime is 20343629. The reversal of 20343621 is 12634302.

It is a happy number.

It is not a de Polignac number, because 20343621 - 2¹ = 20343619 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20343629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31120 + ... + 31766.

It is an arithmetic number, because the mean of its divisors is an integer number (1741824).

Almost surely, 2^20343621 is an apocalyptic number.

It is an amenable number.

20343621 is a deficient number, since it is larger than the sum of its proper divisors (7525563).

20343621 is a wasteful number, since it uses less digits than its factorization.

20343621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 920.

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 20343621 is about 4510.3903378754. The cubic root of 20343621 is about 272.9874942278.

Adding to 20343621 its reverse (12634302), we get a palindrome (32977923).

The spelling of 20343621 in words is "twenty million, three hundred forty-three thousand, six hundred twenty-one".