33421821 has 4 divisors (see below), whose sum is σ = 44562432. Its totient is φ = 22281212.

The previous prime is 33421807. The next prime is 33421837. The reversal of 33421821 is 12812433.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12812433 = 3 ⋅4270811.

It is a cyclic number.

It is not a de Polignac number, because 33421821 - 2¹⁰ = 33420797 is a prime.

It is a super-2 number, since 2×33421821² = 2234036237912082, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 33421791 and 33421800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33421121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5570301 + ... + 5570306.

It is an arithmetic number, because the mean of its divisors is an integer number (11140608).

Almost surely, 2^33421821 is an apocalyptic number.

It is an amenable number.

33421821 is a deficient number, since it is larger than the sum of its proper divisors (11140611).

33421821 is a wasteful number, since it uses less digits than its factorization.

33421821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11140610.

The product of its digits is 1152, while the sum is 24.

The square root of 33421821 is about 5781.1608695832. The cubic root of 33421821 is about 322.1143229208.

It can be divided in two parts, 334 and 21821, that added together give a triangular number (22155 = T₂₁₀).

The spelling of 33421821 in words is "thirty-three million, four hundred twenty-one thousand, eight hundred twenty-one".