21103532 has 12 divisors (see below), whose sum is σ = 38204880. Its totient is φ = 10187856.

The previous prime is 21103531. The next prime is 21103549. The reversal of 21103532 is 23530112.

It is a self number, because there is not a number n which added to its sum of digits gives 21103532.

It is not an unprimeable number, because it can be changed into a prime (21103531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 90848 + ... + 91079.

It is an arithmetic number, because the mean of its divisors is an integer number (3183740).

Almost surely, 2^21103532 is an apocalyptic number.

It is an amenable number.

21103532 is a deficient number, since it is larger than the sum of its proper divisors (17101348).

21103532 is a wasteful number, since it uses less digits than its factorization.

21103532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181960 (or 181958 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 21103532 is about 4593.8580735587. The cubic root of 21103532 is about 276.3450665485.

Adding to 21103532 its reverse (23530112), we get a palindrome (44633644).

The spelling of 21103532 in words is "twenty-one million, one hundred three thousand, five hundred thirty-two".