20782976557225 has 27 divisors (see below), whose sum is σ = 26202043346661. Its totient is φ = 16352723498400.

The previous prime is 20782976557199. The next prime is 20782976557249. The reversal of 20782976557225 is 52275567928702.

The square root of 20782976557225 is 4558835.

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 9573015452841 + 11209961104384 = 3094029^2 + 3348128^2 .

It is not a de Polignac number, because 20782976557225 - 2⁷ = 20782976557097 is a prime.

It is a super-2 number, since 2×20782976557225² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1390437202 + ... + 1390452148.

Almost surely, 2^{20782976557225} is an apocalyptic number.

20782976557225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20782976557225 is the 4558835-th square number.

20782976557225 is the 2279418-th centered octagonal number.

It is an amenable number.

20782976557225 is a deficient number, since it is larger than the sum of its proper divisors (5419066789436).

20782976557225 is an frugal number, since it uses more digits than its factorization.

20782976557225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30026 (or 15013 counting only the distinct ones).

The product of its (nonzero) digits is 296352000, while the sum is 67.

The spelling of 20782976557225 in words is "twenty trillion, seven hundred eighty-two billion, nine hundred seventy-six million, five hundred fifty-seven thousand, two hundred twenty-five".