7221900 has 144 divisors (see below), whose sum is σ = 25276160. Its totient is φ = 1555200.

The previous prime is 7221871. The next prime is 7221911. The reversal of 7221900 is 91227.

It is a happy number.

7221900 is a nontrivial binomial coefficient, being equal to C(3801, 2).

It is a super-2 number, since 2×7221900² = 104311679220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 39810 + ... + 39990.

Almost surely, 2^7221900 is an apocalyptic number.

7221900 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

7221900 is the 3800-th triangular number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7221900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12638080).

7221900 is an abundant number, since it is smaller than the sum of its proper divisors (18054260).

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

7221900 is a wasteful number, since it uses less digits than its factorization.

7221900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224 (or 217 counting only the distinct ones).

The product of its (nonzero) digits is 252, while the sum is 21.

The square root of 7221900 is about 2687.3592986424. The cubic root of 7221900 is about 193.2934585488.

The spelling of 7221900 in words is "seven million, two hundred twenty-one thousand, nine hundred".