4394218261 has 4 divisors (see below), whose sum is σ = 4434532300. Its totient is φ = 4353904224.

The previous prime is 4394218253. The next prime is 4394218267. The reversal of 4394218261 is 1628124934.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2891105361 + 1503112900 = 53769^2 + 38770^2 .

It is a cyclic number.

It is not a de Polignac number, because 4394218261 - 2³ = 4394218253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4394218267) 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, 20156856 + ... + 20157073.

It is an arithmetic number, because the mean of its divisors is an integer number (1108633075).

Almost surely, 2^4394218261 is an apocalyptic number.

It is an amenable number.

4394218261 is a deficient number, since it is larger than the sum of its proper divisors (40314039).

4394218261 is a wasteful number, since it uses less digits than its factorization.

4394218261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40314038.

The product of its digits is 82944, while the sum is 40.

The square root of 4394218261 is about 66288.8999833305. The cubic root of 4394218261 is about 1637.9244839043.

The spelling of 4394218261 in words is "four billion, three hundred ninety-four million, two hundred eighteen thousand, two hundred sixty-one".