3456821 has 2 divisors, whose sum is σ = 3456822. Its totient is φ = 3456820.

The previous prime is 3456793. The next prime is 3456847. The reversal of 3456821 is 1286543.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2436721 + 1020100 = 1561^2 + 1010^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3456821 is a prime.

It is a super-2 number, since 2×3456821² = 23899222852082, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3456881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1728410 + 1728411.

It is an arithmetic number, because the mean of its divisors is an integer number (1728411).

Almost surely, 2^3456821 is an apocalyptic number.

It is an amenable number.

3456821 is a deficient number, since it is larger than the sum of its proper divisors (1).

3456821 is an equidigital number, since it uses as much as digits as its factorization.

3456821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5760, while the sum is 29.

The square root of 3456821 is about 1859.2528069093. The cubic root of 3456821 is about 151.2024972059.

The spelling of 3456821 in words is "three million, four hundred fifty-six thousand, eight hundred twenty-one".