33783378421 has 4 divisors (see below), whose sum is σ = 36382099852. Its totient is φ = 31184656992.

The previous prime is 33783378413. The next prime is 33783378449. The reversal of 33783378421 is 12487338733.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12487338733 = 23 ⋅542927771.

It can be written as a sum of positive squares in 2 ways, for example, as 6653664900 + 27129713521 = 81570^2 + 164711^2 .

It is a cyclic number.

It is not a de Polignac number, because 33783378421 - 2³ = 33783378413 is a prime.

It is a super-2 number, since 2×33783378421² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33783378491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1299360696 + ... + 1299360721.

It is an arithmetic number, because the mean of its divisors is an integer number (9095524963).

Almost surely, 2^33783378421 is an apocalyptic number.

It is an amenable number.

33783378421 is a deficient number, since it is larger than the sum of its proper divisors (2598721431).

33783378421 is a wasteful number, since it uses less digits than its factorization.

33783378421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2598721430.

The product of its digits is 2032128, while the sum is 49.

The spelling of 33783378421 in words is "thirty-three billion, seven hundred eighty-three million, three hundred seventy-eight thousand, four hundred twenty-one".