401788591 has 24 divisors (see below), whose sum is σ = 445882320. Its totient is φ = 360761856.

The previous prime is 401788589. The next prime is 401788637. The reversal of 401788591 is 195887104.

It is a happy number.

It is not a de Polignac number, because 401788591 - 2¹ = 401788589 is a prime.

It is a super-2 number, since 2×401788591² = 322868143715530562, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401788511) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2244540 + ... + 2244718.

It is an arithmetic number, because the mean of its divisors is an integer number (18578430).

Almost surely, 2^401788591 is an apocalyptic number.

401788591 is a deficient number, since it is larger than the sum of its proper divisors (44093729).

401788591 is a wasteful number, since it uses less digits than its factorization.

401788591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411 (or 382 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 43.

The square root of 401788591 is about 20044.6649011651. The cubic root of 401788591 is about 737.9028711807.

The spelling of 401788591 in words is "four hundred one million, seven hundred eighty-eight thousand, five hundred ninety-one".