1210223821 has 16 divisors (see below), whose sum is σ = 1301889024. Its totient is φ = 1122279664.

The previous prime is 1210223797. The next prime is 1210223851. The reversal of 1210223821 is 1283220121.

It is not a de Polignac number, because 1210223821 - 2²⁷ = 1076006093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1210223792 and 1210223801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1210223851) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 110436 + ... + 120898.

It is an arithmetic number, because the mean of its divisors is an integer number (81368064).

Almost surely, 2^1210223821 is an apocalyptic number.

It is an amenable number.

1210223821 is a deficient number, since it is larger than the sum of its proper divisors (91665203).

1210223821 is a wasteful number, since it uses less digits than its factorization.

1210223821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10640.

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 1210223821 is about 34788.2713137632. The cubic root of 1210223821 is about 1065.6679363407.

Adding to 1210223821 its reverse (1283220121), we get a palindrome (2493443942).

The spelling of 1210223821 in words is "one billion, two hundred ten million, two hundred twenty-three thousand, eight hundred twenty-one".