1421221100 has 72 divisors (see below), whose sum is σ = 3329818128. Its totient is φ = 523411200.

The previous prime is 1421221093. The next prime is 1421221111. The reversal of 1421221100 is 11221241.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 605930 + ... + 608270.

It is an arithmetic number, because the mean of its divisors is an integer number (46247474).

Almost surely, 2^1421221100 is an apocalyptic number.

1421221100 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 1421221100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1664909064).

1421221100 is an abundant number, since it is smaller than the sum of its proper divisors (1908597028).

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

1421221100 is a wasteful number, since it uses less digits than its factorization.

1421221100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2835 (or 2828 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 1421221100 is about 37699.0861958218. The cubic root of 1421221100 is about 1124.3129566361.

Adding to 1421221100 its reverse (11221241), we get a palindrome (1432442341).

The spelling of 1421221100 in words is "one billion, four hundred twenty-one million, two hundred twenty-one thousand, one hundred".