213791540 has 12 divisors (see below), whose sum is σ = 448962276. Its totient is φ = 85516608.

The previous prime is 213791527. The next prime is 213791549. The reversal of 213791540 is 45197312.

It can be written as a sum of positive squares in 2 ways, for example, as 136562596 + 77228944 = 11686^2 + 8788^2 .

It is a junction number, because it is equal to n+sod(n) for n = 213791497 and 213791506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213791549) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5344769 + ... + 5344808.

It is an arithmetic number, because the mean of its divisors is an integer number (37413523).

Almost surely, 2^213791540 is an apocalyptic number.

213791540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

213791540 is an abundant number, since it is smaller than the sum of its proper divisors (235170736).

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

213791540 is a wasteful number, since it uses less digits than its factorization.

213791540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10689586 (or 10689584 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 213791540 is about 14621.6120862236. The cubic root of 213791540 is about 597.9481206135.

The spelling of 213791540 in words is "two hundred thirteen million, seven hundred ninety-one thousand, five hundred forty".