249240861 has 8 divisors (see below), whose sum is σ = 369245760. Its totient is φ = 166160556.

The previous prime is 249240847. The next prime is 249240863. The reversal of 249240861 is 168042942.

249240861 is a `hidden beast` number, since 249 + 2 + 408 + 6 + 1 = 666.

It is not a de Polignac number, because 249240861 - 2⁵ = 249240829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (249240863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4615545 + ... + 4615598.

It is an arithmetic number, because the mean of its divisors is an integer number (46155720).

Almost surely, 2^249240861 is an apocalyptic number.

It is an amenable number.

249240861 is a deficient number, since it is larger than the sum of its proper divisors (120004899).

249240861 is an equidigital number, since it uses as much as digits as its factorization.

249240861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9231152 (or 9231146 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 249240861 is about 15787.3639661598. The cubic root of 249240861 is about 629.3222416459.

The spelling of 249240861 in words is "two hundred forty-nine million, two hundred forty thousand, eight hundred sixty-one".