391070987 has 8 divisors (see below), whose sum is σ = 393556800. Its totient is φ = 388591560.

The previous prime is 391070957. The next prime is 391071013. The reversal of 391070987 is 789070193.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 391070987 - 2²⁶ = 323962123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (391070957) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 185264 + ... + 187362.

It is an arithmetic number, because the mean of its divisors is an integer number (49194600).

Almost surely, 2^391070987 is an apocalyptic number.

391070987 is a deficient number, since it is larger than the sum of its proper divisors (2485813).

391070987 is a wasteful number, since it uses less digits than its factorization.

391070987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3193.

The product of its (nonzero) digits is 95256, while the sum is 44.

The square root of 391070987 is about 19775.5148352704. The cubic root of 391070987 is about 731.2825311751.

The spelling of 391070987 in words is "three hundred ninety-one million, seventy thousand, nine hundred eighty-seven".