210123 has 12 divisors (see below), whose sum is σ = 312208. Its totient is φ = 136080.

The previous prime is 210113. The next prime is 210127. The reversal of 210123 is 321012.

It is a happy number.

210123 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It is not a de Polignac number, because 210123 - 2¹² = 206027 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an Ulam number.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (210127) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18 + ... + 648.

2²¹⁰¹²³ is an apocalyptic number.

210123 is a deficient number, since it is larger than the sum of its proper divisors (102085).

210123 is a wasteful number, since it uses less digits than its factorization.

210123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 674 (or 671 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 210123 is about 458.3917538525. The cubic root of 210123 is about 59.4508220627.

Adding to 210123 its reverse (321012), we get a palindrome (531135).

Subtracting 210123 from its reverse (321012), we obtain a square (110889 = 333²).

It can be divided in two parts, 21012 and 3, that multiplied together give a palindrome (63036).

The spelling of 210123 in words is "two hundred ten thousand, one hundred twenty-three", and thus it is an iban number.