20045391 has 8 divisors (see below), whose sum is σ = 26787504. Its totient is φ = 13333440.

The previous prime is 20045387. The next prime is 20045411. The reversal of 20045391 is 19354002.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20045391 - 2² = 20045387 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20045321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5940 + ... + 8681.

It is an arithmetic number, because the mean of its divisors is an integer number (3348438).

Almost surely, 2^20045391 is an apocalyptic number.

20045391 is a deficient number, since it is larger than the sum of its proper divisors (6742113).

20045391 is a wasteful number, since it uses less digits than its factorization.

20045391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15081.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 20045391 is about 4477.2079469241. The cubic root of 20045391 is about 271.6469567209.

Adding to 20045391 its reverse (19354002), we get a palindrome (39399393).

The spelling of 20045391 in words is "twenty million, forty-five thousand, three hundred ninety-one".