20421542421435 has 8 divisors (see below), whose sum is σ = 32674467874320. Its totient is φ = 10891489291424.

The previous prime is 20421542421383. The next prime is 20421542421461. The reversal of 20421542421435 is 53412424512402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20421542421435 - 2¹⁷ = 20421542290363 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20421542421393 and 20421542421402.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 680718080700 + ... + 680718080729.

It is an arithmetic number, because the mean of its divisors is an integer number (4084308484290).

Almost surely, 2^{20421542421435} is an apocalyptic number.

20421542421435 is a deficient number, since it is larger than the sum of its proper divisors (12252925452885).

20421542421435 is a wasteful number, since it uses less digits than its factorization.

20421542421435 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1361436161437.

The product of its (nonzero) digits is 307200, while the sum is 39.

Adding to 20421542421435 its reverse (53412424512402), we get a palindrome (73833966933837).

The spelling of 20421542421435 in words is "twenty trillion, four hundred twenty-one billion, five hundred forty-two million, four hundred twenty-one thousand, four hundred thirty-five".