7218100 has 72 divisors (see below), whose sum is σ = 17186400. Its totient is φ = 2620800.

The previous prime is 7218083. The next prime is 7218121. The reversal of 7218100 is 18127.

7218100 = T₆₉₁ + T₆₉₂ + ... + T₇₁₉.

7218100 is a nontrivial binomial coefficient, being equal to C(3800, 2).

It is a super-2 number, since 2×7218100² = 104201935220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a congruent 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, 55035 + ... + 55165.

It is an arithmetic number, because the mean of its divisors is an integer number (238700).

Almost surely, 2^7218100 is an apocalyptic number.

7218100 is the 3799-th triangular number and also the 1900-th hexagonal number.

7218100 is the 1267-th centered nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7218100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8593200).

7218100 is an abundant number, since it is smaller than the sum of its proper divisors (9968300).

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

7218100 is a wasteful number, since it uses less digits than its factorization.

7218100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193 (or 186 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 19.

The square root of 7218100 is about 2686.6521918551. The cubic root of 7218100 is about 193.2595503894.

The spelling of 7218100 in words is "seven million, two hundred eighteen thousand, one hundred".