21361537227 has 16 divisors (see below), whose sum is σ = 30489264000. Its totient is φ = 13262825664.

The previous prime is 21361537193. The next prime is 21361537231. The reversal of 21361537227 is 72273516312.

It is a de Polignac number, because none of the positive numbers 2^k-21361537227 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21361557227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3172602 + ... + 3179327.

It is an arithmetic number, because the mean of its divisors is an integer number (1905579000).

Almost surely, 2^21361537227 is an apocalyptic number.

21361537227 is a deficient number, since it is larger than the sum of its proper divisors (9127726773).

21361537227 is a wasteful number, since it uses less digits than its factorization.

21361537227 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6352010.

The product of its digits is 105840, while the sum is 39.

The spelling of 21361537227 in words is "twenty-one billion, three hundred sixty-one million, five hundred thirty-seven thousand, two hundred twenty-seven".