20545477 has 2 divisors, whose sum is σ = 20545478. Its totient is φ = 20545476.

The previous prime is 20545433. The next prime is 20545487. The reversal of 20545477 is 77454502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18610596 + 1934881 = 4314^2 + 1391^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20545477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20545487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10272738 + 10272739.

It is an arithmetic number, because the mean of its divisors is an integer number (10272739).

Almost surely, 2^20545477 is an apocalyptic number.

It is an amenable number.

20545477 is a deficient number, since it is larger than the sum of its proper divisors (1).

20545477 is an equidigital number, since it uses as much as digits as its factorization.

20545477 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 39200, while the sum is 34.

The square root of 20545477 is about 4532.7118814237. The cubic root of 20545477 is about 273.8874144519.

Adding to 20545477 its reverse (77454502), we get a palindrome (97999979).

The spelling of 20545477 in words is "twenty million, five hundred forty-five thousand, four hundred seventy-seven".