16503123 has 32 divisors (see below), whose sum is σ = 27553792. Its totient is φ = 8553600.

The previous prime is 16503119. The next prime is 16503131. The reversal of 16503123 is 32130561.

It is not a de Polignac number, because 16503123 - 2² = 16503119 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 16503123.

It is not an unprimeable number, because it can be changed into a prime (16503143) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16158 + ... + 17148.

It is an arithmetic number, because the mean of its divisors is an integer number (861056).

Almost surely, 2^16503123 is an apocalyptic number.

16503123 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

16503123 is a deficient number, since it is larger than the sum of its proper divisors (11050669).

16503123 is a wasteful number, since it uses less digits than its factorization.

16503123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1075.

The product of its (nonzero) digits is 540, while the sum is 21.

The square root of 16503123 is about 4062.4035988562. The cubic root of 16503123 is about 254.5982292902.

Adding to 16503123 its reverse (32130561), we get a palindrome (48633684).

The spelling of 16503123 in words is "sixteen million, five hundred three thousand, one hundred twenty-three".