205984361025 has 81 divisors (see below), whose sum is σ = 374648318499. Its totient is φ = 108184508640.

The previous prime is 205984360973. The next prime is 205984361027. The reversal of 205984361025 is 520163489502.

The square root of 205984361025 is 453855.

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

205984361025 is a `hidden beast` number, since 2 + 0 + 5 + 9 + 8 + 4 + 3 + 610 + 25 = 666.

It can be written as a sum of positive squares in only one way, i.e., 74154369969 + 131829991056 = 272313^2 + 363084^2 .

It is a de Polignac number, because none of the positive numbers 2^k-205984361025 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (205984361027) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 537817984 + ... + 537818366.

Almost surely, 2^205984361025 is an apocalyptic number.

205984361025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

205984361025 is the 453855-th square number.

205984361025 is the 226928-th centered octagonal number.

It is an amenable number.

205984361025 is a deficient number, since it is larger than the sum of its proper divisors (168663957474).

205984361025 is an frugal number, since it uses more digits than its factorization.

205984361025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 940 (or 470 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

It can be divided in two parts, 205984 and 361025, that added together give a square (567009 = 753²).

The spelling of 205984361025 in words is "two hundred five billion, nine hundred eighty-four million, three hundred sixty-one thousand, twenty-five".