21312231232147 has 2 divisors, whose sum is σ = 21312231232148. Its totient is φ = 21312231232146.

The previous prime is 21312231232079. The next prime is 21312231232157. The reversal of 21312231232147 is 74123213221312.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21312231232147 is a prime.

It is a super-2 number, since 2×21312231232147² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21312231232157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10656115616073 + 10656115616074.

It is an arithmetic number, because the mean of its divisors is an integer number (10656115616074).

Almost surely, 2^{21312231232147} is an apocalyptic number.

21312231232147 is a deficient number, since it is larger than the sum of its proper divisors (1).

21312231232147 is an equidigital number, since it uses as much as digits as its factorization.

21312231232147 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 34.

Adding to 21312231232147 its reverse (74123213221312), we get a palindrome (95435444453459).

The spelling of 21312231232147 in words is "twenty-one trillion, three hundred twelve billion, two hundred thirty-one million, two hundred thirty-two thousand, one hundred forty-seven".