20133531 has 24 divisors (see below), whose sum is σ = 32408064. Its totient is φ = 11939760.

The previous prime is 20133527. The next prime is 20133551. The reversal of 20133531 is 13533102.

20133531 is a `hidden beast` number, since 2 + 0 + 133 + 531 = 666.

It is not a de Polignac number, because 20133531 - 2² = 20133527 is a prime.

It is a super-2 number, since 2×20133531² = 810718141055922, which contains 22 as substring.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (20133551) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2490 + ... + 6816.

It is an arithmetic number, because the mean of its divisors is an integer number (1350336).

Almost surely, 2^20133531 is an apocalyptic number.

20133531 is a deficient number, since it is larger than the sum of its proper divisors (12274533).

20133531 is a wasteful number, since it uses less digits than its factorization.

20133531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4391 (or 4388 counting only the distinct ones).

The product of its (nonzero) digits is 270, while the sum is 18.

The square root of 20133531 is about 4487.0403385751. The cubic root of 20133531 is about 272.0445203582.

Adding to 20133531 its reverse (13533102), we get a palindrome (33666633).

The spelling of 20133531 in words is "twenty million, one hundred thirty-three thousand, five hundred thirty-one".