1640380715 has 4 divisors (see below), whose sum is σ = 1968456864. Its totient is φ = 1312304568.

The previous prime is 1640380697. The next prime is 1640380733. The reversal of 1640380715 is 5170830461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5170830461 = 643 ⋅8041727.

It is an interprime number because it is at equal distance from previous prime (1640380697) and next prime (1640380733).

It is a cyclic number.

It is not a de Polignac number, because 1640380715 - 2²⁰ = 1639332139 is a prime.

It is a super-2 number, since 2×1640380715² = 5381697780287822450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 164038067 + ... + 164038076.

It is an arithmetic number, because the mean of its divisors is an integer number (492114216).

Almost surely, 2^1640380715 is an apocalyptic number.

1640380715 is a deficient number, since it is larger than the sum of its proper divisors (328076149).

1640380715 is an equidigital number, since it uses as much as digits as its factorization.

1640380715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 328076148.

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 1640380715 is about 40501.6137332823. The cubic root of 1640380715 is about 1179.3649544275.

The spelling of 1640380715 in words is "one billion, six hundred forty million, three hundred eighty thousand, seven hundred fifteen".