21861311627 has 2 divisors, whose sum is σ = 21861311628. Its totient is φ = 21861311626.

The previous prime is 21861311567. The next prime is 21861311629. The reversal of 21861311627 is 72611316812.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21861311627 is a prime.

Together with 21861311629, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21861311629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10930655813 + 10930655814.

It is an arithmetic number, because the mean of its divisors is an integer number (10930655814).

Almost surely, 2^21861311627 is an apocalyptic number.

21861311627 is a deficient number, since it is larger than the sum of its proper divisors (1).

21861311627 is an equidigital number, since it uses as much as digits as its factorization.

21861311627 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 38.

The spelling of 21861311627 in words is "twenty-one billion, eight hundred sixty-one million, three hundred eleven thousand, six hundred twenty-seven".