391849940 has 24 divisors (see below), whose sum is σ = 824595072. Its totient is φ = 156414240.

The previous prime is 391849921. The next prime is 391849957. The reversal of 391849940 is 49948193.

It is a congruent number.

It is an unprimeable number.

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, 10376 + ... + 29855.

It is an arithmetic number, because the mean of its divisors is an integer number (34358128).

Almost surely, 2^391849940 is an apocalyptic number.

It is an amenable number.

391849940 is an abundant number, since it is smaller than the sum of its proper divisors (432745132).

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

391849940 is a wasteful number, since it uses less digits than its factorization.

391849940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40727 (or 40725 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 47.

The square root of 391849940 is about 19795.1999232137. The cubic root of 391849940 is about 731.7677431104.

The spelling of 391849940 in words is "three hundred ninety-one million, eight hundred forty-nine thousand, nine hundred forty".