249999660 has 36 divisors (see below), whose sum is σ = 758332848. Its totient is φ = 66666528.

The previous prime is 249999649. The next prime is 249999661. The reversal of 249999660 is 66999942.

249999660 is a `hidden beast` number, since 2 + 499 + 9 + 96 + 60 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a junction number, because it is equal to n+sod(n) for n = 249999597 and 249999606.

It is not an unprimeable number, because it can be changed into a prime (249999661) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 694264 + ... + 694623.

Almost surely, 2^249999660 is an apocalyptic number.

249999660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

249999660 is an abundant number, since it is smaller than the sum of its proper divisors (508333188).

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

249999660 is a wasteful number, since it uses less digits than its factorization.

249999660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1388902 (or 1388897 counting only the distinct ones).

The product of its (nonzero) digits is 1889568, while the sum is 54.

The square root of 249999660 is about 15811.3775490942. The cubic root of 249999660 is about 629.9602393652.

The spelling of 249999660 in words is "two hundred forty-nine million, nine hundred ninety-nine thousand, six hundred sixty".