206661904 has 10 divisors (see below), whose sum is σ = 400407470. Its totient is φ = 103330944.

The previous prime is 206661899. The next prime is 206661919. The reversal of 206661904 is 409166602.

It can be written as a sum of positive squares in only one way, i.e., 150111504 + 56550400 = 12252^2 + 7520^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 206661904.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6458169 + ... + 6458200.

It is an arithmetic number, because the mean of its divisors is an integer number (40040747).

Almost surely, 2^206661904 is an apocalyptic number.

It is an amenable number.

206661904 is a deficient number, since it is larger than the sum of its proper divisors (193745566).

206661904 is a wasteful number, since it uses less digits than its factorization.

206661904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12916377 (or 12916371 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 206661904 is about 14375.7401200773. The cubic root of 206661904 is about 591.2259331639.

The spelling of 206661904 in words is "two hundred six million, six hundred sixty-one thousand, nine hundred four".