20133391 has 4 divisors (see below), whose sum is σ = 20193472. Its totient is φ = 20073312.

The previous prime is 20133341. The next prime is 20133397. The reversal of 20133391 is 19333102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19333102 = 2 ⋅9666551.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20133391 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 (20133397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29535 + ... + 30208.

It is an arithmetic number, because the mean of its divisors is an integer number (5048368).

Almost surely, 2^20133391 is an apocalyptic number.

20133391 is a deficient number, since it is larger than the sum of its proper divisors (60081).

20133391 is an equidigital number, since it uses as much as digits as its factorization.

20133391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60080.

The product of its (nonzero) digits is 486, while the sum is 22.

The square root of 20133391 is about 4487.0247380642. The cubic root of 20133391 is about 272.0438897962.

Adding to 20133391 its reverse (19333102), we get a palindrome (39466493).

The spelling of 20133391 in words is "twenty million, one hundred thirty-three thousand, three hundred ninety-one".