641532131 has 4 divisors (see below), whose sum is σ = 675297000. Its totient is φ = 607767264.

The previous prime is 641532097. The next prime is 641532139. The reversal of 641532131 is 131235146.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 641532131 - 2¹⁸ = 641269987 is a prime.

It is a super-2 number, since 2×641532131² = 823126950210802322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 641532131.

It is not an unprimeable number, because it can be changed into a prime (641532139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16882406 + ... + 16882443.

It is an arithmetic number, because the mean of its divisors is an integer number (168824250).

Almost surely, 2^641532131 is an apocalyptic number.

641532131 is a deficient number, since it is larger than the sum of its proper divisors (33764869).

641532131 is a wasteful number, since it uses less digits than its factorization.

641532131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33764868.

The product of its digits is 2160, while the sum is 26.

The square root of 641532131 is about 25328.4845776450. The cubic root of 641532131 is about 862.4610105178.

Adding to 641532131 its reverse (131235146), we get a palindrome (772767277).

The spelling of 641532131 in words is "six hundred forty-one million, five hundred thirty-two thousand, one hundred thirty-one".