249978140 has 12 divisors (see below), whose sum is σ = 524954136. Its totient is φ = 99991248.

The previous prime is 249978133. The next prime is 249978143. The reversal of 249978140 is 41879942.

It is a junction number, because it is equal to n+sod(n) for n = 249978091 and 249978100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (249978143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6249434 + ... + 6249473.

It is an arithmetic number, because the mean of its divisors is an integer number (43746178).

Almost surely, 2^249978140 is an apocalyptic number.

249978140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

249978140 is an abundant number, since it is smaller than the sum of its proper divisors (274975996).

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

249978140 is a wasteful number, since it uses less digits than its factorization.

249978140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12498916 (or 12498914 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 249978140 is about 15810.6970118335. The cubic root of 249978140 is about 629.9421631628.

The spelling of 249978140 in words is "two hundred forty-nine million, nine hundred seventy-eight thousand, one hundred forty".