20311355431 has 2 divisors, whose sum is σ = 20311355432. Its totient is φ = 20311355430.

The previous prime is 20311355423. The next prime is 20311355473. The reversal of 20311355431 is 13455311302.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20311355431 - 2³ = 20311355423 is a prime.

It is a super-2 number, since 2×20311355431² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20311355431.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20311355411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10155677715 + 10155677716.

It is an arithmetic number, because the mean of its divisors is an integer number (10155677716).

Almost surely, 2^20311355431 is an apocalyptic number.

20311355431 is a deficient number, since it is larger than the sum of its proper divisors (1).

20311355431 is an equidigital number, since it uses as much as digits as its factorization.

20311355431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5400, while the sum is 28.

Adding to 20311355431 its reverse (13455311302), we get a palindrome (33766666733).

The spelling of 20311355431 in words is "twenty billion, three hundred eleven million, three hundred fifty-five thousand, four hundred thirty-one".