209721240608 has 48 divisors (see below), whose sum is σ = 474130571040. Its totient is φ = 90310579200.

The previous prime is 209721240601. The next prime is 209721240613. The reversal of 209721240608 is 806042127902.

It is not an unprimeable number, because it can be changed into a prime (209721240601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15672233 + ... + 15685608.

It is an arithmetic number, because the mean of its divisors is an integer number (9877720230).

Almost surely, 2^209721240608 is an apocalyptic number.

It is an amenable number.

209721240608 is an abundant number, since it is smaller than the sum of its proper divisors (264409330432).

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

209721240608 is a wasteful number, since it uses less digits than its factorization.

209721240608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31357881 (or 31357873 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 41.

The spelling of 209721240608 in words is "two hundred nine billion, seven hundred twenty-one million, two hundred forty thousand, six hundred eight".