20207475409 has 9 divisors (see below), whose sum is σ = 22213241449. Its totient is φ = 18369010660.

The previous prime is 20207475331. The next prime is 20207475439. The reversal of 20207475409 is 90457470202.

The square root of 20207475409 is 142153.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 20207475409 - 2⁹ = 20207474897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20207475439) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1557222 + ... + 1570144.

Almost surely, 2^20207475409 is an apocalyptic number.

20207475409 is the 142153-rd square number.

20207475409 is the 71077-th centered octagonal number.

It is an amenable number.

20207475409 is a deficient number, since it is larger than the sum of its proper divisors (2005766040).

20207475409 is an frugal number, since it uses more digits than its factorization.

20207475409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25868 (or 12934 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 40.

It can be divided in two parts, 20207 and 475409, that added together give a square (495616 = 704²).

The spelling of 20207475409 in words is "twenty billion, two hundred seven million, four hundred seventy-five thousand, four hundred nine".