209440684 has 6 divisors (see below), whose sum is σ = 366521204. Its totient is φ = 104720340.

The previous prime is 209440657. The next prime is 209440709. The reversal of 209440684 is 486044902.

It is a super-2 number, since 2×209440684² = 87730800228775712, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26180082 + ... + 26180089.

Almost surely, 2^209440684 is an apocalyptic number.

It is an amenable number.

209440684 is a deficient number, since it is larger than the sum of its proper divisors (157080520).

209440684 is a wasteful number, since it uses less digits than its factorization.

209440684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52360175 (or 52360173 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 37.

The square root of 209440684 is about 14472.0656438533. The cubic root of 209440684 is about 593.8640228073.

It can be divided in two parts, 2094 and 40684, that added together give a triangular number (42778 = T₂₉₂).

The spelling of 209440684 in words is "two hundred nine million, four hundred forty thousand, six hundred eighty-four".