404878991 has 8 divisors (see below), whose sum is σ = 447907968. Its totient is φ = 362887000.

The previous prime is 404878963. The next prime is 404878997. The reversal of 404878991 is 199878404.

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 404878991 - 2¹⁴ = 404862607 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (404878997) 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, 258425 + ... + 259986.

It is an arithmetic number, because the mean of its divisors is an integer number (55988496).

Almost surely, 2^404878991 is an apocalyptic number.

404878991 is a deficient number, since it is larger than the sum of its proper divisors (43028977).

404878991 is a wasteful number, since it uses less digits than its factorization.

404878991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 518493.

The product of its (nonzero) digits is 580608, while the sum is 50.

The square root of 404878991 is about 20121.6050801123. The cubic root of 404878991 is about 739.7899275869.

The spelling of 404878991 in words is "four hundred four million, eight hundred seventy-eight thousand, nine hundred ninety-one".