1640940341 has 4 divisors (see below), whose sum is σ = 1641141612. Its totient is φ = 1640739072.

The previous prime is 1640940331. The next prime is 1640940407. The reversal of 1640940341 is 1430490461.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1430490461 = 12953 ⋅110437.

It can be written as a sum of positive squares in 2 ways, for example, as 1627799716 + 13140625 = 40346^2 + 3625^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1640940341 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1640940298 and 1640940307.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640940331) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87866 + ... + 104891.

It is an arithmetic number, because the mean of its divisors is an integer number (410285403).

Almost surely, 2^1640940341 is an apocalyptic number.

It is an amenable number.

1640940341 is a deficient number, since it is larger than the sum of its proper divisors (201271).

1640940341 is an equidigital number, since it uses as much as digits as its factorization.

1640940341 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201270.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 1640940341 is about 40508.5218318319. The cubic root of 1640940341 is about 1179.4990550554.

The spelling of 1640940341 in words is "one billion, six hundred forty million, nine hundred forty thousand, three hundred forty-one".