20235431477 has 2 divisors, whose sum is σ = 20235431478. Its totient is φ = 20235431476.

The previous prime is 20235431453. The next prime is 20235431497. The reversal of 20235431477 is 77413453202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14256121201 + 5979310276 = 119399^2 + 77326^2 .

It is a cyclic number.

It is not a de Polignac number, because 20235431477 - 2³⁰ = 19161689653 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20235431477.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20235431407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10117715738 + 10117715739.

It is an arithmetic number, because the mean of its divisors is an integer number (10117715739).

Almost surely, 2^20235431477 is an apocalyptic number.

It is an amenable number.

20235431477 is a deficient number, since it is larger than the sum of its proper divisors (1).

20235431477 is an equidigital number, since it uses as much as digits as its factorization.

20235431477 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 141120, while the sum is 38.

Adding to 20235431477 its reverse (77413453202), we get a palindrome (97648884679).

The spelling of 20235431477 in words is "twenty billion, two hundred thirty-five million, four hundred thirty-one thousand, four hundred seventy-seven".