211365660421 has 8 divisors (see below), whose sum is σ = 218689198200. Its totient is φ = 204044460480.

The previous prime is 211365660367. The next prime is 211365660433. The reversal of 211365660421 is 124066563112.

It can be written as a sum of positive squares in 4 ways, for example, as 7554043396 + 203811617025 = 86914^2 + 451455^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 211365660421 - 2¹⁵ = 211365627653 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 (211365660461) 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, 399510 + ... + 763111.

It is an arithmetic number, because the mean of its divisors is an integer number (27336149775).

Almost surely, 2^211365660421 is an apocalyptic number.

It is an amenable number.

211365660421 is a deficient number, since it is larger than the sum of its proper divisors (7323537779).

211365660421 is a wasteful number, since it uses less digits than its factorization.

211365660421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1168919.

The product of its (nonzero) digits is 51840, while the sum is 37.

The spelling of 211365660421 in words is "two hundred eleven billion, three hundred sixty-five million, six hundred sixty thousand, four hundred twenty-one".