641440031 has 8 divisors (see below), whose sum is σ = 671161344. Its totient is φ = 611871480.

The previous prime is 641440027. The next prime is 641440061. The reversal of 641440031 is 130044146.

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 641440031 - 2² = 641440027 is a prime.

It is a super-2 number, since 2×641440031² = 822890626738561922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a junction number, because it is equal to n+sod(n) for n = 641439979 and 641440006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641440061) 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, 29555 + ... + 46436.

It is an arithmetic number, because the mean of its divisors is an integer number (83895168).

Almost surely, 2^641440031 is an apocalyptic number.

641440031 is a deficient number, since it is larger than the sum of its proper divisors (29721313).

641440031 is a wasteful number, since it uses less digits than its factorization.

641440031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76381.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 641440031 is about 25326.6664012459. Note that the first 3 decimals coincide. The cubic root of 641440031 is about 862.4197361702.

Adding to 641440031 its reverse (130044146), we get a palindrome (771484177).

The spelling of 641440031 in words is "six hundred forty-one million, four hundred forty thousand, thirty-one".