20501425452421 has 12 divisors (see below), whose sum is σ = 20814261552000. Its totient is φ = 20193223872360.

The previous prime is 20501425452413. The next prime is 20501425452449. The reversal of 20501425452421 is 12425452410502.

It is not a de Polignac number, because 20501425452421 - 2³ = 20501425452413 is a prime.

It is a super-2 number, since 2×20501425452421² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20501425452401) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 41551830 + ... + 42042328.

It is an arithmetic number, because the mean of its divisors is an integer number (1734521796000).

Almost surely, 2^{20501425452421} is an apocalyptic number.

It is an amenable number.

20501425452421 is a deficient number, since it is larger than the sum of its proper divisors (312836099579).

20501425452421 is an frugal number, since it uses more digits than its factorization.

20501425452421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 499944 (or 499877 counting only the distinct ones).

The product of its (nonzero) digits is 128000, while the sum is 37.

Adding to 20501425452421 its reverse (12425452410502), we get a palindrome (32926877862923).

The spelling of 20501425452421 in words is "twenty trillion, five hundred one billion, four hundred twenty-five million, four hundred fifty-two thousand, four hundred twenty-one".