20531236 has 12 divisors (see below), whose sum is σ = 39196080. Its totient is φ = 9332360.

The previous prime is 20531219. The next prime is 20531243. The reversal of 20531236 is 63213502.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 233266 + ... + 233353.

It is an arithmetic number, because the mean of its divisors is an integer number (3266340).

Almost surely, 2^20531236 is an apocalyptic number.

It is an amenable number.

20531236 is a deficient number, since it is larger than the sum of its proper divisors (18664844).

20531236 is a wasteful number, since it uses less digits than its factorization.

20531236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 466634 (or 466632 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 22.

The square root of 20531236 is about 4531.1406952334. The cubic root of 20531236 is about 273.8241185708.

Adding to 20531236 its reverse (63213502), we get a palindrome (83744738).

The spelling of 20531236 in words is "twenty million, five hundred thirty-one thousand, two hundred thirty-six".