20111530 has 16 divisors (see below), whose sum is σ = 37043424. Its totient is φ = 7857360.

The previous prime is 20111501. The next prime is 20111563. The reversal of 20111530 is 3511102.

It is a self number, because there is not a number n which added to its sum of digits gives 20111530.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22956 + ... + 23815.

It is an arithmetic number, because the mean of its divisors is an integer number (2315214).

Almost surely, 2^20111530 is an apocalyptic number.

20111530 is a deficient number, since it is larger than the sum of its proper divisors (16931894).

20111530 is a wasteful number, since it uses less digits than its factorization.

20111530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46821.

The product of its (nonzero) digits is 30, while the sum is 13.

The square root of 20111530 is about 4484.5880524302. The cubic root of 20111530 is about 271.9453916468.

Adding to 20111530 its reverse (3511102), we get a palindrome (23622632).

The spelling of 20111530 in words is "twenty million, one hundred eleven thousand, five hundred thirty".