206721481135680 has 336 divisors, whose sum is σ = 847943269864704. Its totient is φ = 45196249190400.

The previous prime is 206721481135679. The next prime is 206721481135681. The reversal of 206721481135680 is 86531184127602.

It is a happy number.

206721481135680 is a `hidden beast` number, since 2 + 0 + 6 + 7 + 21 + 48 + 1 + 13 + 568 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (206721481135679) and next prime (206721481135681).

It is a tau number, because it is divible by the number of its divisors (336).

It is not an unprimeable number, because it can be changed into a prime (206721481135681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 222450271 + ... + 223377630.

Almost surely, 2^{206721481135680} is an apocalyptic number.

206721481135680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

206721481135680 is an abundant number, since it is smaller than the sum of its proper divisors (641221788729024).

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

206721481135680 is a wasteful number, since it uses less digits than its factorization.

206721481135680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 445827954 (or 445827941 counting only the distinct ones).

The product of its (nonzero) digits is 3870720, while the sum is 54.

The spelling of 206721481135680 in words is "two hundred six trillion, seven hundred twenty-one billion, four hundred eighty-one million, one hundred thirty-five thousand, six hundred eighty".