202536901681 has 27 divisors (see below), whose sum is σ = 225108366763. Its totient is φ = 182176596800.

The previous prime is 202536901673. The next prime is 202536901691. The reversal of 202536901681 is 186109635202.

The square root of 202536901681 is 450041.

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

It can be written as a sum of positive squares in only one way, i.e., 157684439025 + 44852462656 = 397095^2 + 211784^2 .

It is not a de Polignac number, because 202536901681 - 2³ = 202536901673 is a prime.

It is a super-2 number, since 2×202536901681² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (202536901601) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 175965456 + ... + 175966606.

Almost surely, 2^202536901681 is an apocalyptic number.

202536901681 is the 450041-st square number.

202536901681 is the 225021-st centered octagonal number.

It is an amenable number.

202536901681 is a deficient number, since it is larger than the sum of its proper divisors (22571465082).

202536901681 is an frugal number, since it uses more digits than its factorization.

202536901681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2382 (or 1191 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 43.

The spelling of 202536901681 in words is "two hundred two billion, five hundred thirty-six million, nine hundred one thousand, six hundred eighty-one".