206721521006 has 64 divisors (see below), whose sum is σ = 421604628480. Its totient is φ = 73404264960.

The previous prime is 206721520979. The next prime is 206721521047. The reversal of 206721521006 is 600125127602.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 495371 + ... + 811686.

It is an arithmetic number, because the mean of its divisors is an integer number (6587572320).

Almost surely, 2^206721521006 is an apocalyptic number.

206721521006 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

206721521006 is an abundant number, since it is smaller than the sum of its proper divisors (214883107474).

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

206721521006 is a wasteful number, since it uses less digits than its factorization.

206721521006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1307169.

The product of its (nonzero) digits is 10080, while the sum is 32.

Adding to 206721521006 its reverse (600125127602), we get a palindrome (806846648608).

It can be divided in two parts, 206721 and 521006, that added together give a palindrome (727727).

The spelling of 206721521006 in words is "two hundred six billion, seven hundred twenty-one million, five hundred twenty-one thousand, six".