1231165550431 has 2 divisors, whose sum is σ = 1231165550432. Its totient is φ = 1231165550430.

The previous prime is 1231165550369. The next prime is 1231165550443. The reversal of 1231165550431 is 1340555611321.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1231165550431 - 2²¹ = 1231163453279 is a prime.

It is a super-2 number, since 2×1231165550431² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1231165550831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615582775215 + 615582775216.

It is an arithmetic number, because the mean of its divisors is an integer number (615582775216).

Almost surely, 2^{1231165550431} is an apocalyptic number.

1231165550431 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231165550431 is an equidigital number, since it uses as much as digits as its factorization.

1231165550431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54000, while the sum is 37.

The spelling of 1231165550431 in words is "one trillion, two hundred thirty-one billion, one hundred sixty-five million, five hundred fifty thousand, four hundred thirty-one".