33978421 has 4 divisors (see below), whose sum is σ = 34328812. Its totient is φ = 33628032.

The previous prime is 33978419. The next prime is 33978433. The reversal of 33978421 is 12487933.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 23415921 + 10562500 = 4839^2 + 3250^2 .

It is a cyclic number.

It is not a de Polignac number, because 33978421 - 2¹ = 33978419 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33978221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 175050 + ... + 175243.

It is an arithmetic number, because the mean of its divisors is an integer number (8582203).

Almost surely, 2^33978421 is an apocalyptic number.

It is an amenable number.

33978421 is a deficient number, since it is larger than the sum of its proper divisors (350391).

33978421 is an equidigital number, since it uses as much as digits as its factorization.

33978421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 350390.

The product of its digits is 36288, while the sum is 37.

The square root of 33978421 is about 5829.1012171689. The cubic root of 33978421 is about 323.8926287769.

The spelling of 33978421 in words is "thirty-three million, nine hundred seventy-eight thousand, four hundred twenty-one".