20343435421 has 4 divisors (see below), whose sum is σ = 20382482844. Its totient is φ = 20304388000.

The previous prime is 20343435419. The next prime is 20343435457. The reversal of 20343435421 is 12453434302.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12453434302 = 2 ⋅6226717151.

It can be written as a sum of positive squares in 2 ways, for example, as 8438443321 + 11904992100 = 91861^2 + 109110^2 .

It is a cyclic number.

It is not a de Polignac number, because 20343435421 - 2¹ = 20343435419 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20343435461) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19522930 + ... + 19523971.

It is an arithmetic number, because the mean of its divisors is an integer number (5095620711).

Almost surely, 2^20343435421 is an apocalyptic number.

It is an amenable number.

20343435421 is a deficient number, since it is larger than the sum of its proper divisors (39047423).

20343435421 is an equidigital number, since it uses as much as digits as its factorization.

20343435421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39047422.

The product of its (nonzero) digits is 34560, while the sum is 31.

Adding to 20343435421 its reverse (12453434302), we get a palindrome (32796869723).

The spelling of 20343435421 in words is "twenty billion, three hundred forty-three million, four hundred thirty-five thousand, four hundred twenty-one".