206661367772640 has 768 divisors, whose sum is σ = 824049113610240. Its totient is φ = 47882423255040.

The previous prime is 206661367772623. The next prime is 206661367772653. The reversal of 206661367772640 is 46277763166602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1351915092 + ... + 1352067948.

It is an arithmetic number, because the mean of its divisors is an integer number (1072980616680).

Almost surely, 2^{206661367772640} is an apocalyptic number.

206661367772640 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 206661367772640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (412024556805120).

206661367772640 is an abundant number, since it is smaller than the sum of its proper divisors (617387745837600).

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

206661367772640 is a wasteful number, since it uses less digits than its factorization.

206661367772640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154152 (or 154138 counting only the distinct ones).

The product of its (nonzero) digits is 128024064, while the sum is 63.

The spelling of 206661367772640 in words is "two hundred six trillion, six hundred sixty-one billion, three hundred sixty-seven million, seven hundred seventy-two thousand, six hundred forty".