20545501445461 has 2 divisors, whose sum is σ = 20545501445462. Its totient is φ = 20545501445460.

The previous prime is 20545501445459. The next prime is 20545501445549. The reversal of 20545501445461 is 16454410554502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12862659467025 + 7682841978436 = 3586455^2 + 2771794^2 .

It is a cyclic number.

It is not a de Polignac number, because 20545501445461 - 2¹ = 20545501445459 is a prime.

Together with 20545501445459, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20545501445761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10272750722730 + 10272750722731.

It is an arithmetic number, because the mean of its divisors is an integer number (10272750722731).

Almost surely, 2^{20545501445461} is an apocalyptic number.

It is an amenable number.

20545501445461 is a deficient number, since it is larger than the sum of its proper divisors (1).

20545501445461 is an equidigital number, since it uses as much as digits as its factorization.

20545501445461 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1920000, while the sum is 46.

Adding to 20545501445461 its reverse (16454410554502), we get a palindrome (36999911999963).

The spelling of 20545501445461 in words is "twenty trillion, five hundred forty-five billion, five hundred one million, four hundred forty-five thousand, four hundred sixty-one".