206144123640 has 1024 divisors, whose sum is σ = 841928048640. Its totient is φ = 39140720640.

The previous prime is 206144123599. The next prime is 206144123659. The reversal of 206144123640 is 46321441602.

It is a happy number.

It is a super-2 number, since 2×206144123640² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 650296762 + ... + 650297078.

It is an arithmetic number, because the mean of its divisors is an integer number (822195360).

Almost surely, 2^206144123640 is an apocalyptic number.

206144123640 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 206144123640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (420964024320).

206144123640 is an abundant number, since it is smaller than the sum of its proper divisors (635783925000).

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

206144123640 is a wasteful number, since it uses less digits than its factorization.

206144123640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512 (or 508 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 33.

The spelling of 206144123640 in words is "two hundred six billion, one hundred forty-four million, one hundred twenty-three thousand, six hundred forty".