1640065531 has 32 divisors (see below), whose sum is σ = 1959648768. Its totient is φ = 1357171200.

The previous prime is 1640065529. The next prime is 1640065591. The reversal of 1640065531 is 1355600461.

It is not a de Polignac number, because 1640065531 - 2¹ = 1640065529 is a prime.

It is a super-2 number, since 2×1640065531² = 5379629891948623922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1640065493 and 1640065502.

It is not an unprimeable number, because it can be changed into a prime (1640065591) 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 31 ways as a sum of consecutive naturals, for example, 1559956 + ... + 1561006.

It is an arithmetic number, because the mean of its divisors is an integer number (61239024).

Almost surely, 2^1640065531 is an apocalyptic number.

1640065531 is a deficient number, since it is larger than the sum of its proper divisors (319583237).

1640065531 is a wasteful number, since it uses less digits than its factorization.

1640065531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1411.

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 1640065531 is about 40497.7225409035. The cubic root of 1640065531 is about 1179.2894148957.

Adding to 1640065531 its reverse (1355600461), we get a palindrome (2995665992).

The spelling of 1640065531 in words is "one billion, six hundred forty million, sixty-five thousand, five hundred thirty-one".