12356551381 has 2 divisors, whose sum is σ = 12356551382. Its totient is φ = 12356551380.

The previous prime is 12356551343. The next prime is 12356551399. The reversal of 12356551381 is 18315565321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10648382481 + 1708168900 = 103191^2 + 41330^2 .

It is a cyclic number.

It is not a de Polignac number, because 12356551381 - 2⁷ = 12356551253 is a prime.

It is a super-2 number, since 2×12356551381² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12356551321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6178275690 + 6178275691.

It is an arithmetic number, because the mean of its divisors is an integer number (6178275691).

Almost surely, 2^12356551381 is an apocalyptic number.

It is an amenable number.

12356551381 is a deficient number, since it is larger than the sum of its proper divisors (1).

12356551381 is an equidigital number, since it uses as much as digits as its factorization.

12356551381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108000, while the sum is 40.

The spelling of 12356551381 in words is "twelve billion, three hundred fifty-six million, five hundred fifty-one thousand, three hundred eighty-one".