1640730939 has 8 divisors (see below), whose sum is σ = 2193839952. Its totient is φ = 1090721280.

The previous prime is 1640730913. The next prime is 1640730947. The reversal of 1640730939 is 9390370461.

1640730939 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1640730939 - 2¹³ = 1640722747 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1640730939.

It is not an unprimeable number, because it can be changed into a prime (1640735939) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 773602 + ... + 775719.

It is an arithmetic number, because the mean of its divisors is an integer number (274229994).

Almost surely, 2^1640730939 is an apocalyptic number.

1640730939 is a deficient number, since it is larger than the sum of its proper divisors (553109013).

1640730939 is a wasteful number, since it uses less digits than its factorization.

1640730939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1549677.

The product of its (nonzero) digits is 122472, while the sum is 42.

The square root of 1640730939 is about 40505.9370833462. The cubic root of 1640730939 is about 1179.4488805788.

The spelling of 1640730939 in words is "one billion, six hundred forty million, seven hundred thirty thousand, nine hundred thirty-nine".