3420421 has 2 divisors, whose sum is σ = 3420422. Its totient is φ = 3420420.

The previous prime is 3420409. The next prime is 3420427. The reversal of 3420421 is 1240243.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2340900 + 1079521 = 1530^2 + 1039^2 .

It is a cyclic number.

It is not a de Polignac number, because 3420421 - 2⁷ = 3420293 is a prime.

It is a pancake number, because a pancake can be divided into 3420421 parts by 2615 straight cuts.

3420421 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 3420395 and 3420404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3420427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1710210 + 1710211.

It is an arithmetic number, because the mean of its divisors is an integer number (1710211).

Almost surely, 2^3420421 is an apocalyptic number.

It is an amenable number.

3420421 is a deficient number, since it is larger than the sum of its proper divisors (1).

3420421 is an equidigital number, since it uses as much as digits as its factorization.

3420421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 3420421 is about 1849.4380227518. The cubic root of 3420421 is about 150.6699074102.

Adding to 3420421 its reverse (1240243), we get a palindrome (4660664).

It can be divided in two parts, 34204 and 21, that added together give a square (34225 = 185²).

The spelling of 3420421 in words is "three million, four hundred twenty thousand, four hundred twenty-one".