209123664 has 40 divisors (see below), whose sum is σ = 572016960. Its totient is φ = 65607168.

The previous prime is 209123641. The next prime is 209123687. The reversal of 209123664 is 466321902.

It is an interprime number because it is at equal distance from previous prime (209123641) and next prime (209123687).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 127324 + ... + 128955.

It is an arithmetic number, because the mean of its divisors is an integer number (14300424).

Almost surely, 2^209123664 is an apocalyptic number.

209123664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

209123664 is an abundant number, since it is smaller than the sum of its proper divisors (362893296).

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

209123664 is a wasteful number, since it uses less digits than its factorization.

209123664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 256307 (or 256301 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 33.

The square root of 209123664 is about 14461.1086711912. The cubic root of 209123664 is about 593.5642373041.

The spelling of 209123664 in words is "two hundred nine million, one hundred twenty-three thousand, six hundred sixty-four".