209138976 has 48 divisors (see below), whose sum is σ = 609991200. Its totient is φ = 69712704.

The previous prime is 209138953. The next prime is 209138999. The reversal of 209138976 is 679831902.

It is an interprime number because it is at equal distance from previous prime (209138953) and next prime (209138999).

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×209138976² = 87478222564657152, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 120166 + ... + 121893.

It is an arithmetic number, because the mean of its divisors is an integer number (12708150).

Almost surely, 2^209138976 is an apocalyptic number.

It is an amenable number.

209138976 is an abundant number, since it is smaller than the sum of its proper divisors (400852224).

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

209138976 is a wasteful number, since it uses less digits than its factorization.

209138976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242078 (or 242064 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The square root of 209138976 is about 14461.6380814899. The cubic root of 209138976 is about 593.5787238422.

The spelling of 209138976 in words is "two hundred nine million, one hundred thirty-eight thousand, nine hundred seventy-six".