20051331 has 16 divisors (see below), whose sum is σ = 28429056. Its totient is φ = 12542816.

The previous prime is 20051329. The next prime is 20051351. The reversal of 20051331 is 13315002.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20051331 - 2¹ = 20051329 is a prime.

It is a super-2 number, since 2×20051331² = 804111749743122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20051331.

It is not an unprimeable number, because it can be changed into a prime (20051351) 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 15 ways as a sum of consecutive naturals, for example, 916 + ... + 6398.

It is an arithmetic number, because the mean of its divisors is an integer number (1776816).

Almost surely, 2^20051331 is an apocalyptic number.

20051331 is a deficient number, since it is larger than the sum of its proper divisors (8377725).

20051331 is a wasteful number, since it uses less digits than its factorization.

20051331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5562.

The product of its (nonzero) digits is 90, while the sum is 15.

The square root of 20051331 is about 4477.8712576402. The cubic root of 20051331 is about 271.6737862228.

Adding to 20051331 its reverse (13315002), we get a palindrome (33366333).

The spelling of 20051331 in words is "twenty million, fifty-one thousand, three hundred thirty-one".