33011921 has 2 divisors, whose sum is σ = 33011922. Its totient is φ = 33011920.

The previous prime is 33011903. The next prime is 33011941. The reversal of 33011921 is 12911033.

It is an a-pointer prime, because the next prime (33011941) can be obtained adding 33011921 to its sum of digits (20).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21715600 + 11296321 = 4660^2 + 3361^2 .

It is an emirp because it is prime and its reverse (12911033) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 33011921 - 2¹⁰ = 33010897 is a prime.

It is a super-2 number, since 2×33011921² = 2179573856220482, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 33011893 and 33011902.

It is not a weakly prime, because it can be changed into another prime (33011941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16505960 + 16505961.

It is an arithmetic number, because the mean of its divisors is an integer number (16505961).

Almost surely, 2^33011921 is an apocalyptic number.

It is an amenable number.

33011921 is a deficient number, since it is larger than the sum of its proper divisors (1).

33011921 is an equidigital number, since it uses as much as digits as its factorization.

33011921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 20.

The square root of 33011921 is about 5745.6001427179. The cubic root of 33011921 is about 320.7920515990.

Adding to 33011921 its reverse (12911033), we get a palindrome (45922954).

The spelling of 33011921 in words is "thirty-three million, eleven thousand, nine hundred twenty-one".