201685520500 has 24 divisors (see below), whose sum is σ = 440481177864. Its totient is φ = 80674208000.

The previous prime is 201685520497. The next prime is 201685520503. The reversal of 201685520500 is 5025586102.

It is an interprime number because it is at equal distance from previous prime (201685520497) and next prime (201685520503).

It can be written as a sum of positive squares in 4 ways, for example, as 14470416 + 201671050084 = 3804^2 + 449078^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201685520503) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 201685021 + ... + 201686020.

It is an arithmetic number, because the mean of its divisors is an integer number (18353382411).

Almost surely, 2^201685520500 is an apocalyptic number.

201685520500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201685520500 is an abundant number, since it is smaller than the sum of its proper divisors (238795657364).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

201685520500 is a wasteful number, since it uses less digits than its factorization.

201685520500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403371060 (or 403371048 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 34.

The spelling of 201685520500 in words is "two hundred one billion, six hundred eighty-five million, five hundred twenty thousand, five hundred".