213261005 has 8 divisors (see below), whose sum is σ = 270967032. Its totient is φ = 160572928.

The previous prime is 213260981. The next prime is 213261017. The reversal of 213261005 is 500162312.

It can be written as a sum of positive squares in 4 ways, for example, as 35545444 + 177715561 = 5962^2 + 13331^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213261005 is a prime.

It is a super-2 number, since 2×213261005² = 90960512507220050, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1254392 + ... + 1254561.

It is an arithmetic number, because the mean of its divisors is an integer number (33870879).

Almost surely, 2^213261005 is an apocalyptic number.

It is an amenable number.

213261005 is a deficient number, since it is larger than the sum of its proper divisors (57706027).

213261005 is a wasteful number, since it uses less digits than its factorization.

213261005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2508975.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 213261005 is about 14603.4586656723. The cubic root of 213261005 is about 597.4530976296.

The spelling of 213261005 in words is "two hundred thirteen million, two hundred sixty-one thousand, five".