213727540 has 72 divisors (see below), whose sum is σ = 499436280. Its totient is φ = 76737024.

The previous prime is 213727511. The next prime is 213727541. The reversal of 213727540 is 45727312.

It can be written as a sum of positive squares in 12 ways, for example, as 108951844 + 104775696 = 10438^2 + 10236^2 .

It is a super-2 number, since 2×213727540² = 91358922708903200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213727541) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 124206 + ... + 125914.

It is an arithmetic number, because the mean of its divisors is an integer number (6936615).

Almost surely, 2^213727540 is an apocalyptic number.

213727540 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 213727540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (249718140).

213727540 is an abundant number, since it is smaller than the sum of its proper divisors (285708740).

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

213727540 is a wasteful number, since it uses less digits than its factorization.

213727540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1781 (or 1766 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 31.

The square root of 213727540 is about 14619.4233812418. The cubic root of 213727540 is about 597.8884480013. Note that the first 3 decimals are identical.

The spelling of 213727540 in words is "two hundred thirteen million, seven hundred twenty-seven thousand, five hundred forty".