204537697981 has 48 divisors (see below), whose sum is σ = 235183698288. Its totient is φ = 177135206400.

The previous prime is 204537697957. The next prime is 204537697999. The reversal of 204537697981 is 189796735402.

It can be written as a sum of positive squares in 8 ways, for example, as 22592795481 + 181944902500 = 150309^2 + 426550^2 .

It is not a de Polignac number, because 204537697981 - 2²³ = 204529309373 is a prime.

It is a super-2 number, since 2×204537697981² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204537694981) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 60638011 + ... + 60641383.

It is an arithmetic number, because the mean of its divisors is an integer number (4899660381).

It is a 1-persistent number, because it is pandigital, but 2⋅204537697981 = 409075395962 is not.

Almost surely, 2^204537697981 is an apocalyptic number.

It is an amenable number.

204537697981 is a deficient number, since it is larger than the sum of its proper divisors (30646000307).

204537697981 is a wasteful number, since it uses less digits than its factorization.

204537697981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3710 (or 3691 counting only the distinct ones).

The product of its (nonzero) digits is 22861440, while the sum is 61.

The spelling of 204537697981 in words is "two hundred four billion, five hundred thirty-seven million, six hundred ninety-seven thousand, nine hundred eighty-one".