213765641 has 8 divisors (see below), whose sum is σ = 221781000. Its totient is φ = 205793280.

The previous prime is 213765631. The next prime is 213765649. The reversal of 213765641 is 146567312.

It can be written as a sum of positive squares in 4 ways, for example, as 77810041 + 135955600 = 8821^2 + 11660^2 .

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

It is not a de Polignac number, because 213765641 - 2¹⁴ = 213749257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213765649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 440 + ... + 20681.

It is an arithmetic number, because the mean of its divisors is an integer number (27722625).

Almost surely, 2^213765641 is an apocalyptic number.

It is an amenable number.

213765641 is a deficient number, since it is larger than the sum of its proper divisors (8015359).

213765641 is a wasteful number, since it uses less digits than its factorization.

213765641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21499.

The product of its digits is 30240, while the sum is 35.

The square root of 213765641 is about 14620.7264183419. The cubic root of 213765641 is about 597.9239742203.

The spelling of 213765641 in words is "two hundred thirteen million, seven hundred sixty-five thousand, six hundred forty-one".