1640401445 has 16 divisors (see below), whose sum is σ = 1984715568. Its totient is φ = 1301544960.

The previous prime is 1640401439. The next prime is 1640401457. The reversal of 1640401445 is 5441040461.

It can be written as a sum of positive squares in 8 ways, for example, as 466516801 + 1173884644 = 21599^2 + 34262^2 .

It is not a de Polignac number, because 1640401445 - 2¹⁶ = 1640335909 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 307037 + ... + 312333.

It is an arithmetic number, because the mean of its divisors is an integer number (124044723).

Almost surely, 2^1640401445 is an apocalyptic number.

It is an amenable number.

1640401445 is a deficient number, since it is larger than the sum of its proper divisors (344314123).

1640401445 is a wasteful number, since it uses less digits than its factorization.

1640401445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5800.

The product of its (nonzero) digits is 7680, while the sum is 29.

The square root of 1640401445 is about 40501.8696482027. The cubic root of 1640401445 is about 1179.3699224069.

The spelling of 1640401445 in words is "one billion, six hundred forty million, four hundred one thousand, four hundred forty-five".