20637333649 has 9 divisors (see below), whose sum is σ = 20866372401. Its totient is φ = 20410786560.

The previous prime is 20637333593. The next prime is 20637333653. The reversal of 20637333649 is 94633373602.

The square root of 20637333649 is 143657.

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

It can be written as a sum of positive squares in 4 ways, for example, as 311699025 + 20325634624 = 17655^2 + 142568^2 .

It is not a de Polignac number, because 20637333649 - 2¹⁷ = 20637202577 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20637333599 and 20637333608.

It is not an unprimeable number, because it can be changed into a prime (20637333659) 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, 13933989 + ... + 13935469.

Almost surely, 2^20637333649 is an apocalyptic number.

20637333649 is the 143657-th square number.

20637333649 is the 71829-th centered octagonal number.

It is an amenable number.

20637333649 is a deficient number, since it is larger than the sum of its proper divisors (229038752).

20637333649 is an frugal number, since it uses more digits than its factorization.

20637333649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3156 (or 1578 counting only the distinct ones).

The product of its (nonzero) digits is 1469664, while the sum is 46.

The spelling of 20637333649 in words is "twenty billion, six hundred thirty-seven million, three hundred thirty-three thousand, six hundred forty-nine".