1210221000 has 320 divisors, whose sum is σ = 4312788480. Its totient is φ = 316483200.

The previous prime is 1210220989. The next prime is 1210221013. The reversal of 1210221000 is 1220121.

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

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 5426889 + ... + 5427111.

It is an arithmetic number, because the mean of its divisors is an integer number (13477464).

Almost surely, 2^1210221000 is an apocalyptic number.

1210221000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1210221000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2156394240).

1210221000 is an abundant number, since it is smaller than the sum of its proper divisors (3102567480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1210221000 is a wasteful number, since it uses less digits than its factorization.

1210221000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323 (or 300 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 1210221000 is about 34788.2307684654. The cubic root of 1210221000 is about 1065.6671083254.

Adding to 1210221000 its reverse (1220121), we get a palindrome (1211441121).

It can be divided in two parts, 1 and 210221000, that added together give a square (210221001 = 14499²).

The spelling of 1210221000 in words is "one billion, two hundred ten million, two hundred twenty-one thousand".