20500435477 has 2 divisors, whose sum is σ = 20500435478. Its totient is φ = 20500435476.

The previous prime is 20500435447. The next prime is 20500435481. The reversal of 20500435477 is 77453400502.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16628360401 + 3872075076 = 128951^2 + 62226^2 .

It is a cyclic number.

It is not a de Polignac number, because 20500435477 - 2³¹ = 18352951829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20500435427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10250217738 + 10250217739.

It is an arithmetic number, because the mean of its divisors is an integer number (10250217739).

Almost surely, 2^20500435477 is an apocalyptic number.

It is an amenable number.

20500435477 is a deficient number, since it is larger than the sum of its proper divisors (1).

20500435477 is an equidigital number, since it uses as much as digits as its factorization.

20500435477 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 117600, while the sum is 37.

Adding to 20500435477 its reverse (77453400502), we get a palindrome (97953835979).

The spelling of 20500435477 in words is "twenty billion, five hundred million, four hundred thirty-five thousand, four hundred seventy-seven".