20612421 has 8 divisors (see below), whose sum is σ = 30536960. Its totient is φ = 13741596.

The previous prime is 20612419. The next prime is 20612429. The reversal of 20612421 is 12421602.

It is not a de Polignac number, because 20612421 - 2¹ = 20612419 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20612394 and 20612403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20612429) 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 7 ways as a sum of consecutive naturals, for example, 381685 + ... + 381738.

It is an arithmetic number, because the mean of its divisors is an integer number (3817120).

Almost surely, 2^20612421 is an apocalyptic number.

It is an amenable number.

20612421 is a deficient number, since it is larger than the sum of its proper divisors (9924539).

20612421 is an equidigital number, since it uses as much as digits as its factorization.

20612421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 763432 (or 763426 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 20612421 is about 4540.0904176018. The cubic root of 20612421 is about 274.1845640560.

The spelling of 20612421 in words is "twenty million, six hundred twelve thousand, four hundred twenty-one".