205964499840 has 256 divisors, whose sum is σ = 718272576000. Its totient is φ = 49785937920.

The previous prime is 205964499791. The next prime is 205964499841. The reversal of 205964499840 is 48994469502.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205964499841) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7356909 + ... + 7384851.

It is an arithmetic number, because the mean of its divisors is an integer number (2805752250).

Almost surely, 2^205964499840 is an apocalyptic number.

205964499840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205964499840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (359136288000).

205964499840 is an abundant number, since it is smaller than the sum of its proper divisors (512308076160).

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

205964499840 is a wasteful number, since it uses less digits than its factorization.

205964499840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28325 (or 28313 counting only the distinct ones).

The product of its (nonzero) digits is 22394880, while the sum is 60.

The spelling of 205964499840 in words is "two hundred five billion, nine hundred sixty-four million, four hundred ninety-nine thousand, eight hundred forty".