20731275 has 24 divisors (see below), whose sum is σ = 38085360. Its totient is φ = 11056320.

The previous prime is 20731273. The next prime is 20731283. The reversal of 20731275 is 57213702.

It is not a de Polignac number, because 20731275 - 2¹ = 20731273 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20731273) 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 23 ways as a sum of consecutive naturals, for example, 14682 + ... + 16031.

It is an arithmetic number, because the mean of its divisors is an integer number (1586890).

Almost surely, 2^20731275 is an apocalyptic number.

20731275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20731275 is a deficient number, since it is larger than the sum of its proper divisors (17354085).

20731275 is a wasteful number, since it uses less digits than its factorization.

20731275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30732 (or 30721 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 27.

The square root of 20731275 is about 4553.1609899058. The cubic root of 20731275 is about 274.7105494409.

Adding to 20731275 its reverse (57213702), we get a palindrome (77944977).

The spelling of 20731275 in words is "twenty million, seven hundred thirty-one thousand, two hundred seventy-five".