21627367091 has 36 divisors (see below), whose sum is σ = 24815577384. Its totient is φ = 18846698640.

The previous prime is 21627367081. The next prime is 21627367103. The reversal of 21627367091 is 19076372612.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It is a de Polignac number, because none of the positive numbers 2^k-21627367091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21627367051) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 155592500 + ... + 155592638.

It is an arithmetic number, because the mean of its divisors is an integer number (689321594).

Almost surely, 2^21627367091 is an apocalyptic number.

21627367091 is a deficient number, since it is larger than the sum of its proper divisors (3188210293).

21627367091 is an frugal number, since it uses more digits than its factorization.

21627367091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 369 (or 179 counting only the distinct ones).

The product of its (nonzero) digits is 190512, while the sum is 44.

Multiplying 21627367091 by its sum of digits (44), we get a square (951604152004 = 975502²).

The spelling of 21627367091 in words is "twenty-one billion, six hundred twenty-seven million, three hundred sixty-seven thousand, ninety-one".