33820421 has 2 divisors, whose sum is σ = 33820422. Its totient is φ = 33820420.

The previous prime is 33820379. The next prime is 33820433. The reversal of 33820421 is 12402833.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31528225 + 2292196 = 5615^2 + 1514^2 .

It is a cyclic number.

It is not a de Polignac number, because 33820421 - 2¹⁰ = 33819397 is a prime.

It is a super-2 number, since 2×33820421² = 2287641753234482, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (33820471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16910210 + 16910211.

It is an arithmetic number, because the mean of its divisors is an integer number (16910211).

Almost surely, 2^33820421 is an apocalyptic number.

It is an amenable number.

33820421 is a deficient number, since it is larger than the sum of its proper divisors (1).

33820421 is an equidigital number, since it uses as much as digits as its factorization.

33820421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 33820421 is about 5815.5327357001. The cubic root of 33820421 is about 323.3898139426.

The spelling of 33820421 in words is "thirty-three million, eight hundred twenty thousand, four hundred twenty-one".