401908791 has 8 divisors (see below), whose sum is σ = 538418944. Its totient is φ = 266668920.

The previous prime is 401908789. The next prime is 401908807. The reversal of 401908791 is 197809104.

It is a happy number.

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

It is not a de Polignac number, because 401908791 - 2¹ = 401908789 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 (401908751) 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, 316831 + ... + 318096.

It is an arithmetic number, because the mean of its divisors is an integer number (67302368).

Almost surely, 2^401908791 is an apocalyptic number.

401908791 is a deficient number, since it is larger than the sum of its proper divisors (136510153).

401908791 is a wasteful number, since it uses less digits than its factorization.

401908791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 635141.

The product of its (nonzero) digits is 18144, while the sum is 39.

The square root of 401908791 is about 20047.6629810060. The cubic root of 401908791 is about 737.9764480847.

The spelling of 401908791 in words is "four hundred one million, nine hundred eight thousand, seven hundred ninety-one".