213228122591 has 4 divisors (see below), whose sum is σ = 232612497384. Its totient is φ = 193843747800.

The previous prime is 213228122543. The next prime is 213228122609. The reversal of 213228122591 is 195221822312.

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

It is a cyclic number.

It is not a de Polignac number, because 213228122591 - 2¹⁰ = 213228121567 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 (213228122501) 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, 9692187380 + ... + 9692187401.

It is an arithmetic number, because the mean of its divisors is an integer number (58153124346).

Almost surely, 2^213228122591 is an apocalyptic number.

213228122591 is a deficient number, since it is larger than the sum of its proper divisors (19384374793).

213228122591 is a wasteful number, since it uses less digits than its factorization.

213228122591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19384374792.

The product of its digits is 34560, while the sum is 38.

The spelling of 213228122591 in words is "two hundred thirteen billion, two hundred twenty-eight million, one hundred twenty-two thousand, five hundred ninety-one".