6401421 has 12 divisors (see below), whose sum is σ = 9957948. Its totient is φ = 3939264.

The previous prime is 6401419. The next prime is 6401459. The reversal of 6401421 is 1241046.

6401421 is a `hidden beast` number, since 640 + 1 + 4 + 21 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1512900 + 4888521 = 1230^2 + 2211^2 .

It is not a de Polignac number, because 6401421 - 2¹ = 6401419 is a prime.

6401421 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 6401394 and 6401403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6401411) 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, 27240 + ... + 27473.

It is an arithmetic number, because the mean of its divisors is an integer number (829829).

Almost surely, 2^6401421 is an apocalyptic number.

It is an amenable number.

6401421 is a deficient number, since it is larger than the sum of its proper divisors (3556527).

6401421 is a wasteful number, since it uses less digits than its factorization.

6401421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54732 (or 54729 counting only the distinct ones).

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

The square root of 6401421 is about 2530.1029623318. The cubic root of 6401421 is about 185.6772933646.

Adding to 6401421 its reverse (1241046), we get a palindrome (7642467).

The spelling of 6401421 in words is "six million, four hundred one thousand, four hundred twenty-one".