20235656513 has 2 divisors, whose sum is σ = 20235656514. Its totient is φ = 20235656512.

The previous prime is 20235656489. The next prime is 20235656521. The reversal of 20235656513 is 31565653202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15323468944 + 4912187569 = 123788^2 + 70087^2 .

It is a cyclic number.

It is not a de Polignac number, because 20235656513 - 2¹² = 20235652417 is a prime.

It is not a weakly prime, because it can be changed into another prime (20235656533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10117828256 + 10117828257.

It is an arithmetic number, because the mean of its divisors is an integer number (10117828257).

Almost surely, 2^20235656513 is an apocalyptic number.

It is an amenable number.

20235656513 is a deficient number, since it is larger than the sum of its proper divisors (1).

20235656513 is an equidigital number, since it uses as much as digits as its factorization.

20235656513 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162000, while the sum is 38.

The spelling of 20235656513 in words is "twenty billion, two hundred thirty-five million, six hundred fifty-six thousand, five hundred thirteen".