210021123 has 16 divisors (see below), whose sum is σ = 302673056. Its totient is φ = 128770560.

The previous prime is 210021121. The next prime is 210021143. The reversal of 210021123 is 321120012.

It is not a de Polignac number, because 210021123 - 2¹ = 210021121 is a prime.

It is a super-2 number, since 2×210021123² = 88217744212362258, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210021099 and 210021108.

It is not an unprimeable number, because it can be changed into a prime (210021121) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 1083 + ... + 20523.

It is an arithmetic number, because the mean of its divisors is an integer number (18917066).

Almost surely, 2^210021123 is an apocalyptic number.

210021123 is a deficient number, since it is larger than the sum of its proper divisors (92651933).

210021123 is a wasteful number, since it uses less digits than its factorization.

210021123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19734.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 210021123 is about 14492.1055406038. The cubic root of 210021123 is about 594.4121237293.

Adding to 210021123 its reverse (321120012), we get a palindrome (531141135).

The spelling of 210021123 in words is "two hundred ten million, twenty-one thousand, one hundred twenty-three".