209979145488 has 40 divisors (see below), whose sum is σ = 619938430528. Its totient is φ = 59994041472.

The previous prime is 209979145469. The next prime is 209979145489. The reversal of 209979145488 is 884541979902.

It is not an unprimeable number, because it can be changed into a prime (209979145489) 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, 312468631 + ... + 312469302.

Almost surely, 2^209979145488 is an apocalyptic number.

209979145488 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

209979145488 is an abundant number, since it is smaller than the sum of its proper divisors (409959285040).

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

209979145488 is a wasteful number, since it uses less digits than its factorization.

209979145488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 624937951 (or 624937945 counting only the distinct ones).

The product of its (nonzero) digits is 52254720, while the sum is 66.

The spelling of 209979145488 in words is "two hundred nine billion, nine hundred seventy-nine million, one hundred forty-five thousand, four hundred eighty-eight".