213665400 has 288 divisors, whose sum is σ = 808385760. Its totient is φ = 50181120.

The previous prime is 213665369. The next prime is 213665429. The reversal of 213665400 is 4566312.

213665400 is a `hidden beast` number, since 2 + 1 + 3 + 6 + 654 + 0 + 0 = 666.

213665400 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×213665400³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 538002 + ... + 538398.

It is an arithmetic number, because the mean of its divisors is an integer number (2806895).

Almost surely, 2^213665400 is an apocalyptic number.

213665400 is a gapful number since it is divisible by the number (20) 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 213665400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (404192880).

213665400 is an abundant number, since it is smaller than the sum of its proper divisors (594720360).

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

213665400 is a wasteful number, since it uses less digits than its factorization.

213665400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 455 (or 443 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 213665400 is about 14617.2979719235. The cubic root of 213665400 is about 597.8304982250.

The spelling of 213665400 in words is "two hundred thirteen million, six hundred sixty-five thousand, four hundred".