1640928973 has 2 divisors, whose sum is σ = 1640928974. Its totient is φ = 1640928972.

The previous prime is 1640928917. The next prime is 1640929049. The reversal of 1640928973 is 3798290461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 929213289 + 711715684 = 30483^2 + 26678^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1640928973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1640958973) 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 as a sum of consecutive naturals, namely, 820464486 + 820464487.

It is an arithmetic number, because the mean of its divisors is an integer number (820464487).

Almost surely, 2^1640928973 is an apocalyptic number.

It is an amenable number.

1640928973 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640928973 is an equidigital number, since it uses as much as digits as its factorization.

1640928973 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 653184, while the sum is 49.

The square root of 1640928973 is about 40508.3815154346. The cubic root of 1640928973 is about 1179.4963312968.

The spelling of 1640928973 in words is "one billion, six hundred forty million, nine hundred twenty-eight thousand, nine hundred seventy-three".