20112551609 has 2 divisors, whose sum is σ = 20112551610. Its totient is φ = 20112551608.

The previous prime is 20112551531. The next prime is 20112551629. The reversal of 20112551609 is 90615521102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18801894400 + 1310657209 = 137120^2 + 36203^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20112551609 is a prime.

It is not a weakly prime, because it can be changed into another prime (20112551629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10056275804 + 10056275805.

It is an arithmetic number, because the mean of its divisors is an integer number (10056275805).

Almost surely, 2^20112551609 is an apocalyptic number.

It is an amenable number.

20112551609 is a deficient number, since it is larger than the sum of its proper divisors (1).

20112551609 is an equidigital number, since it uses as much as digits as its factorization.

20112551609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5400, while the sum is 32.

The spelling of 20112551609 in words is "twenty billion, one hundred twelve million, five hundred fifty-one thousand, six hundred nine".